International Conference MarCoastEcos2012, Tirana, Albania, 25-28 April 2012
Plenary lecture
COMMUNITY ARCHITECTURE AND ECOSYSTEM PROCESSES IN MEDITERRANEAN LAGOONS *
Alberto Basset, Ilaria Rosati
Department of Biological and Environmental Sciences and Technologies, University of Salento – 73100 Lecce, Italy * E-mail: alberto.basset@unisalento.it Abstract
Biodiversity and ecosystem functioning --- Oral presentations ---
Top-down and bottom up approaches have been applied to explain community organisation and ecosystem processes. Here, following a hierarchical structure of ecosystems highlighting the relevance of high-level constraints, we focus on the common structural patterns of benthic communities and the relationships with key ecosystem processes, constituting the general architecture of ecological communities in Mediterranean lagoons. To this aim, we have approached a description of biodiversity in lagoon ecosystem on a biogeographical along the Mediterranean coasts. The description was downscaled at the landscape level focusing on the different benthic habitat types and addressing the relationships between biodiversity and functional diversity, on the one hand and ecosystem processes and properties, on the other. We searched for common patterns in biodiversity within and among scales and for bottom up (species trait based) vs. top-down (ecosystem property based) explanations. Rarity, redundancy and singularity are key properties of benthic macroinvertebrate guilds at every geographical area, affecting and diversity. At every area a high regional biodiversity is determined by a large number of rare species and a high dissimilarity among lagoons. Life cycle traits and the behaviour of larval stages, at the species level, as well as lagoon openness and vigour, at the ecosystem level, seem to have a major role to explain the difference in patterns of biodiversity between study areas at a biogeographical scale. The same species and ecosystem level properties, together with spatial patchiness, seem also to be key factors downscaling biodiversity analysis at the landscape level. The analysis performed support the scaling of biodiversity in lagoon ecosystems, which results from cumulative integrations of rare species with narrow ranges across spatial and temporal scales. The analysis also suggests that ecosystem properties, as openness and vigour, determining connectivity and overall niche space, have a major role to explain biodiversity at the different scale considered. Keywords: community architecture, ecosystem processes, Mediterranean lagoons
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Proceedings
Oral presentations: Biodiversity and ecosystem functioning
International Conference MarCoastEcos2012, Tirana, Albania, 25-28 April 2012
Plenary lecture
THE CYST BANK IN THE MARINE SEDIMENTS OF THE VLORA BAY (ALBANIA)
BIODIVERSITY AND ENVIRONMENTAL ADAPTABILITY IN TRANSITIONAL WATERS
1
Fernando Rubino, 2Salvatore Moscatello, 2Manuela Belmonte, 2 Gianmarco Ingrosso, *2Genuario Belmonte
*1
Sofia Reizopoulou, 2Georgios Fyttis, 3Eva Papastergiadou, 1 Kalliopi Sigala, 4Alberto Basset, 5Artemis Nicolaidou
1
IAMC, CNR, UOS Talassografico “A. Cerruti�, 74100 Taranto, Italy Lab. of Zoogeography and Fauna, CoNISMa U.O. Lecce, DiSTeBA University of the Salento, 73100 Lecce, Italy. *E-mail: genuario.belmonte@unisalento.it
2
1
Hellenic Centre for Marine Research, Institute of Oceanography, PO Box 712, 190 13 Anavyssos, Attiki, Greece 2 Oceanography Center of Cyprus, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus 3 Department of Biology, Section of Plant Biology, University of Patras, GR 26 500 University Campus Patras, Greece 4 DiSTeBA, University of Salento, SP Lecce Monteroni 73100 Lecce, Italy 5 Department of Zoology Marine Biology, School of Biology, University of Athens, 15784 Panepistimiopoli, Athens, Greece *E-mail: sreiz@hcmr.gr Abstract Comparative study of different Mediterranean lagoons has indicated that seawater influence has the primary control in determining the diversity level of these ecosystems. It is mainly the marine influence which structures the environmental gradient, with species richness following a single-scale pattern. The main groups forming the communities are the widely occurring, specialised in inhabiting the transition zone. However, the presence of the marine group within restricted ranges help in increasing the species richness of each ecosystem. Many anthropogenic interventions influencing the hydrological characteristics of coastal lagoons (i.e. damming) further affect the relationships between marine water influence and the biological zoning.
Abstract In the framework of the INTERREG III project CISM, sediment cores were collected at two stations in Gulf of Vlora to study the assemblages of cysts produced by plankton. A total of 87 different cyst morphotypes were identified, mostly produced by Dinophyta together with Ciliophora, Rotifera and planktonic Crustacea. In 22 cases the cyst belonged to a species not reported from the plankton during a contemporaneous study of the water column. About the taxonomic composition, the most abundant cysts were the calcareous ones produced by Scrippsiella species (Dinophyta). Other calcareous-walled cysts were identified as fossil species described from Pleistocene to Pliocene strata. They were found also in surface sediments and this finding together with the successful germination obtained for some of them prove their modern status. Total abundances generally decreased with sediment depth at station 40, rd th while an irregular trend characterized the station 45 which showed distinctive maxima at 3 and 8 cm below the sediment surface. In addition different species showed peaks of abundance at different depths in the sediment. The present work represents the first study on the bank of plankton resting stages existing in the marine sediments of the Vlora bay. The study confirmed the utility of such a kind of investigation for a more correct evaluation of the species diversity. The different distribution along the sediment depth, in addition, suggests that this field could be of topical importance in the assessment of the story of species assemblages variability. Keywords: Resting stages, Gulf of Vlora, South-East Europe, Mediterranean Sea, Plankton Resilience, Cyst banks.
Keywords: coastal lagoons, species richness, biodiversity patterns, biological zoning
Introduction Resting stages (cysts) produced by plankton organisms in temperate seas accumulate in bottom sediments of confined coastal areas (Belmonte et al., 1995). They represent biodiversity reservoirs which sustain high resilience capacity of plankton communities, fueling them with recruits of propagules at each return of favourable conditions, according to the so-called Supply Vertical Ecology model (Marcus & Boero, 1998). The existence of benthic stages in the life cycles of holoplankton gives a new interpretation key in the understanding of life cycles role in the pelagic-benthic coupling of coastal sea (Giangrande et al., 1994; Boero et al., 1996). As a consequence, the assessment of the biodiversity at each marine site should consider the unexpressed fraction of the plankton community which stays in the bottom sediments, by performing integrated sampling programs (Moscatello et al., 2004; Rubino et al., 2009). Notwithstanding this ascertained importance of cyst banks in the coastal marine ecology, the topic resting vs activity of plankters has commonly been considered for single taxa, and only scantly from the whole community point of view. This has been probably due to the great complexity (compositional, functional, and distributional) of cyst banks. In fact, it has been demonstrated that the species assemblages in bottom sediments (as resting stages, or cysts) at each time are quite different from those collectable in the water column (as active stages) (Rubino et al., 1998; 2009). The study of marine cyst banks, however, is complex due to different points of view. Cysts share a common morphological plan (Belmonte et al., 1997) even if belonging to organisms from different realms. The cyst morphology is usually convergent and consequently sharply different from that of active stages. In fact, in some cases their identification is very problematic. But it is also true that for some naked dinoflagellates or with a similar thecal plates pattern, cyst could be quite different, allowing a correct identification without the use of SEM or molecular techniques. Species producing cysts show different life cycle lengths and/or timing in cyst production. The rest capability of cysts is different too. They are Proceedings
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Oral presentations: Biodiversity and ecosystem functioning
International Conference MarCoastEcos2012, Tirana, Albania, 25-28 April 2012
generally programmed to rest for the duration of the adverse period, but fractions of them can also rest for extra-long periods, allowing the population to travel over time for decades (Marcus et al., 1994; Jiang et al., 2004; Dahms et al., 2006; for copepods; Belmonte et al., 1999; Ribeiro et al., 2011; for dinoflagellates). Hairston et al. (1995), although for freshwater species, reported a rest of more than 300 years for a Calanoida egg. The particularly scant literature existing about the whole cyst bank community, encouraged us to describe situations in any part of the Mediterranean, with the aim to obtain a rich data set on which to base models and experimental situations. The present study, in addition, has been programmed for an Albanian bay, a geographic area in general poorly studied from the marine biodiversity point of view. The present data will be compared also with those deriving from water column analysis of phytoplankton and microzooplankton (Moscatello et al., 2011) to assess with more precision the biodiversity of the plankton in the Vlora bay.
Sampling procedure Samples of bottom sediments were collected in three replicates using a Van Veen grab with upper windows that allowed the collection of undisturbed sediment cores. At each station, 2 different PVC corers have been used (h: 30 cm; inner : 4 and 8 cm) for the analysis of cysts produced by phyto- and zooplankton, respectively. Sediment cores obtained were immediately subdivided into 1 cm thick layers, until 15th cm from the sediment surface. The margin of each layer was discarded to avoid the contamination of material from the upper strata during the insertion of the corer into the sediments. Once obtained, the samples were stored in the dark at 5°C, until the treatment in the laboratory. Different methodologies were used to extract from sediments cysts produced by phytoplankton and zooplankton. This differentiation has been necessary because phytoplankton’s cysts are more abundant then zooplankton ones and have different types of cyst walls (calcareous, siliceous, organic) that create complexity to the procedure when the whole cyst bank is studied. So, the most fruitful method of separation from the sediment is to use a filtration technique through meshes of different sizes. On the contrary, zooplankton’s resting stages are less abundant, and their walls are only organic, allowing the adoption of a centrifugation method coupled with the filtration, to obtain a “clean” sample from a relatively great quantity of sediment.
Materials and methods Study site An oceanographic campaign has been carried out in the Vlora bay from 17th to 23rd of January 2008 aboard the o.v. “Universitatis” of the CoNISMa. This survey was in the framework of the Project PIC Interreg III Italy-Albania for the technical assistance to the management of an International Centre of Marine Sciences in Albania (CISM). In order to investigate the presence and distribution of resting stages produced by planktonic species in the area, 2 stations were chosen, representing two different typologies of environment: a deep zone (station 40, depth: 54 m), of terrigenous mud dominated by the presence of Labidoplax digitata (Holothuroidea), and a shallower site (Station 45, depth: 28 m), of terrigenous mud dominated by Turritella communis (Gastropoda) (Figure 1) (for the classification of mud biocenoses of the Vlora Bay, see Maiorano et al., 2011).
Phytoplankton cysts (20-125 μm) In the laboratory the samples were treated according to a sieving technique basically consisting of the following steps: the entire sample is homogenized and then subsampled, obtaining of 3-5 ml of wet sediment which are screened through a 20 µm mesh (Endecott’s LTD steel sieves, ISO3310-1, London, England), using natural filtered (0.45 μm) seawater (Taranto Bay). the retained fraction is ultrasonicated for 1 min and screened again through a sieve battery (125, 75 and 20 µm mesh sizes), obtaining a fine-grained fraction containing protistan cysts (20-75 µm), a 75-125 µm fraction with larger dinoflagellate resting stages (e.g. Lingulodinium spp.), and zooplankton resting eggs. The material retained onto the 125 µm mesh is discarded. No chemicals were used to disaggregate sediment particles in order to avoid the dissolution of calcareous and siliceous cyst walls. Qualitative and quantitative analyses were carried out under an inverted microscope (Zeiss Axiovert S100 equipped with a Nikon Coolpix 990 digital camera) at 200 and 320 magnifications. Both full (i.e. presumably viable) and empty (germinated) cysts were considered. At least 1/5 of the sample was analysed for the finest fraction, whereas the >75 µm fraction was entirely examined. All the recognised resting stage morphotypes were identified on the basis of published descriptions and germination experiments. Identification was performed at species level. When this was not possible, higher taxa were considered. As a rule, the modern, biological names were used. Only for morphotypes whose active stage is not known, the paleontological name has been reported. A fixed aliquot of sediment from each sample was oven-dried at 70°C for 24 h to calculate the water content and obtain quantitative data for each taxon as cysts x g-1 of dry sediment. Zooplankton resting eggs (45-200 μm) In this case the Onbè (1978) method was used, slightly modified using 45 and 200 μm mesh sizes to obtain a size range typical of mesozooplankton resting eggs. For each sample a fixed quantity of wet sediment has been treated (45 cm3). Only viable resting eggs were counted and quantitative data for each taxon are reported as resting eggs x 100g-1 of dry sediment. Germination experiments To achieve germination, single viable (full) cysts and resting eggs were isolated using a micropipette and placed into Nunclon microwells (Nalge Nunc International, Roskilde, Denmark) containing ≈1 ml of natural sterilised seawater. Cysts were incubated at 20°C, 12:12 h LD cycle and 100 μE m-2 sec-1 irradiance, and daily examined until germination, or discharged after 30 days of unsuccessful incubation.
Figure 1. Map of the study area with the localization of the two investigated sampling stations (n.40, n.45) in the Gulf of Vlora (Albania)
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Data analysis Resting stages abundance from surface sediments of the two study sites was obtained merging the data coming from the three replicates of the two sets of samples (those for phytoplankton and zooplankton resting stages). Density values are expressed as cysts x g -1 of dry sediment. For stratigraphic analysis, only the data from the zooplankton fraction (45-200 μm) were used just to facilitate and speed the analysis. In this case density values are expressed as cysts 100 g-1 of dry sediment. From abundance matrix (taxa vs stations and taxa vs station and cm respectively) of both surface sediments and stratigraphy, the Bray-Curtis similarity was calculated after 4th root transformation in order to allow rare species to become more evident. The PRIMER function DIVERSE (Primer-E Ltd, Plymouth, UK) was used to calculate taxonomic richness (S), taxon abundance (N), Margalef (d) and Shannon-Wiener diversity (H’) and Pielou’s evenness (J’), for each sample. Relationships between the samples collected at the two stations were analyzed by means of a non-metric multidimensional scaling (nMDS) with superimposed the hierarchical clustering with a cut at 60% (for surface sediments) and 70% (for stratigraphy) of similarity, while the SIMPER routine was used to identify % dissimilarity and the taxa that mostly contributed to the differences. Moreover, the statistical significance of the differences between the two stations was calculated by means of a 2-way crossed analysis of similarities (ANOSIM) on the Bray-Curtis similarity matrix from stratigraphy. All univariate and multivariate analyses were performed using PRIMER v.6 package (Primer-E Ltd, Plymouth, UK).
Follisdinellum splendidum Versteegh Gonyaulax group Gymnodinium impudicum (Fraga & Bravo) G. Hansen & Möestrup Gymnodinium nolleri Ellegaard & Möestrup Gymnodinium sp.1 Lingulodinium polyedrum (Stein) Dodge Melodomuncula berlinensis Versteegh Nematodinium armatum (Dogiel) Kofoid & Swezy Oblea rotunda (Lebour) Balech ex Sournia Pentapharsodinium dalei Indelicato & Loeblich type 1 Pentapharsodinium dalei Indelicato & Loeblich type 2 Pentapharsodinium tyrrhenicum Montresor, Zingone & Marino type 1 Pentapharsodinium tyrrhenicum Montresor, Zingone & Marino type 2 Polykrikos kofoidii Chatton Polykrikos schwartzii Bütschli Protoperidinium compressum (Abé) Balech Protoperidinium conicum (Gran) Balech Protoperidinium oblongum (Aurivillius) Parke & Dodge Protoperidinium parthenopes Zingone & Montresor Protoperidinium steidingerae Balech Protoperidinium subinerme (Paulsen) Loeblich III Protoperidinium thorianum (Paulsen) Balech Protoperidinium sp.1 Protoperidinium sp.5 Protoperidinium sp.6 Pyrophacus horologium Stein Scrippsiella cf. crystallina Lewis Scrippsiella lachrymosa Lewis Scrippsiella ramonii Montresor Scrippsiella trochoidea (Stein) Loeblich rough type Scrippsiella trochoidea (Stein) Loeblich smooth type Scrippsiella trochoidea (Stein) Loeblich large type Scrippsiella trochoidea (Stein) Loeblich medium type Scrippsiella trochoidea (Stein) Loeblich small type Scrippsiella sp.1 Scrippsiella sp.4 Scrippsiella sp.5 Scrippsiella sp.6 Scrippsiella sp.8 Thoracosphaera sp. Dinophyta sp.2 Dinophyta sp.7 Dinophyta sp.17 Dinophyta sp.26 Dinophyta sp.30 Dinophyta sp.33 Ciliates Codonella aspera Kofoid & Campbell Codonella orthoceras Heackel Codonellopsis monacensis (Rampi) Balech Codonellopsis schabii (Brandt) Kofoid & Campbell Epiplocylis undella (Ostenfeld & Schmidt) Jörgensen
Results Total biodiversity Resting stages were found at all the levels along the sediment core columns from the two investigated sites in the Vlora bay. Merging the data coming from the two set of samples (20-125 μm and 45-200 μm) and considering both viable and germinated forms from each station, 87 different resting stage morphotypes produced by plankton were recognized (Table 1). Most of them (59, in representation of 20 genera) were dinoflagellates, 16 were ciliates (9 genera), 4 rotifers (2 genera), 5 crustaceans (4 genera), while 3 (1 cyst type and 2 resting eggs) remained unidentified. Station 40 showed the highest biodiversity with 79 morphotypes, 35 of them exclusive. At Station 45, 52 cyst morphotypes were observed, 8 of them exclusive of the site. Moreover, the analysis of the germinated cysts for the fraction 20-125 μm, allowed the discovery of 11 types not observed as viable, all produced by dinoflagellates. Table 1. List of the resting stage (cyst) morphotypes recovered from sediments of Gulf of Vlora (Albania). cysts observed as viable (i.e. full), cysts observed as germinated (i.e. empty). St. 40
taxon Dinoflagellates Alexandrium minutum Halim Alexandrium tamarense (Lebour) Balech Alexandrium sp.1 Alexandrium sp.2 Bicarinellum tricarinelloides Versteegh Calcicarpinum perfectum Versteegh Calciodinellum albatrosianum (Kamptner) Janofske & Karwath Calciodinellum operosum (Deflandre) Montresor Calciperidinium asymmetricum Versteegh Cochlodinium polykrikoides Margalef type 1 Cochlodinium polykrikoides Margalef type 2 Diplopelta parva (Abé) Matsuoka Diplopsalis lenticula Bergh Proceedings
St. 45
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Oral presentations: Biodiversity and ecosystem functioning Rabdonella spiralis (Fol) Brandt Stenosemella ventricosa (Claparède & Lachmann) Jörgensen Strobilidium sp. Strombidium cf. acutum (Leegaard) Kahl Strombidium conicum (Lohman) Wulff Tintinnopsis beroidea Stein Tintinnopsis butschlii Kofoid & Campbell Tintinnopsis campanula Ehrenberg Tintinnopsis cylindrica Daday Tintinnopsis radix (Imhof) Undella claparedei (Entz) Daday Rotifers Brachionus plicatilis Müller Synchaeta sp. spiny type Synchaeta sp. rough type Synchaeta sp. mucous type Crustaceans Cladocerans Penilia avirostris Dana Crustaceans Copepods Acartia clausi/margalefi Acartia sp.1 Centropages sp. Paracartia latisetosa (Krizcaguin) Unidentified Cyst type 1 Resting Egg 1 Resting Egg 9
International Conference MarCoastEcos2012, Tirana, Albania, 25-28 April 2012
available data, Station 40 showed a higher biodiversity, both in terms of number of taxa and values of diversity indexes (see Table 3), even if total densities, expressed as cysts g -1 of dry sediment were comparable, with 389 ±127 cysts g-1 (average ± s.d.) at Station 40 vs 329 ±123 cysts g-1 at Station 45. Assemblages were 58% dissimilar between the two sites (SIMPER, Table 4).
a
b
Comparison with plankton A study on the plankton composition (Moscatello et al., 2011) was carried out in the same area on samples collected during the same scientific cruise. In January 2008, the phytoplankton and the microzooplankton hosted a total of 178 categories. Considering only the main cyst producers (dinoflagellates, and ciliates), the examination of the water column of 16 different stations gave a total of 76 taxa (48 dinoflagellates, 28 ciliates). The present analysis of sediments, from just 2 stations, gave a total of 75 taxa among dinoflagellates and ciliates. This singular proximity of values, however, did not correspond with the taxa composition of the two compartments. In fact, 36 cysts were identified as a taxon lacking from the plankton list of that same period (January 2008). This number could be higher if we consider only the plankton stations close to the 2 sediment ones. The present data can be compared also with those of Rubino et al (2009) relatively to the another Albanian gulf. In that study a total of 58 cyst morphotypes were found in 7 different stations in the gulf of Drin. Also due to nomenclature problems, uncertainty of identification, and difference in examined periods, only in very few cases it was possible to ascertain the contemporaneous presence of the species in both plankton and benthon compartments. Not rare were the cases of impossibile identification due to the new morphology encountered. Experiments of germination, in such cases, gave the possibility to attribute the cyst to a high level taxon at least, as the case of a Strombidium (Ciliofora) whose cyst morphology has been here reported for the first time (see Figure 2). Surface sediments The analysis of surface sediments, i.e. those most interested by events of cyst deposition and cyst resuspension/germination, revealed sharp differences between the two stations. In total 36 different cyst types were observed in this first layer (Table 2), 23 produced by dinoflagellates, 6 by ciliates, 2 by rotifers, 4 by crustaceans, 1 undetermined. Even with caution due to the few Proceedings
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c Figure 2. Photographs of a Ciliofora cyst, with two, opposite, papulae (a). Its empty shell (the hatch occurres from one of the two papulae) (b). the germling active stage, a Strombidium ciliate (c)
The most abundant cyst morphotypes were calcareous cysts produced by species of Calciodinellaceae family (dinoflagellates). At Station 40 five cyst types of this family accounted for 95% of the total abundance, while at Station 45 only one cyst type, Scrippsiella trochoidea medium type, was responsible for 99%, confirming the lower equitability at this station. The nMDS ordination (Figure 3, stress=0) with superimposed the hierarchical cluster with a cut at 60% of similarity, clearly reflects a separation between the samples from Station 40 and those from Station 45. Among these the sample 45b, due to its higher diversity, segregates more close to the samples of Station 40. Vertical distribution into the sediment At both the investigated stations, a general decrease of total abundances was observed with the depth along the sediment core columns. At Station 40 higher values of total abundance and diversity than Station 45 were registered (Figure 4) even if they were decuplicated at different depths. In particular, highest abundances were registered at 2nd and 4th cm, while Shannon index peaked at 7th and 10th cm. At Station 45 maximum abundance was registered in the top 5 cm layers with a the decrease below, which was not mirrored by the diversity that remained quite constant along the entire core.
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Oral presentations: Biodiversity and ecosystem functioning
International Conference MarCoastEcos2012, Tirana, Albania, 25-28 April 2012
-1
Table 2. Abundance (cysts g dw) of viable resting stages (cysts) observed in surface sediments of the two stations in Gulf of Vlora (Albania). The values from the three replicates are reported. 40a
40b
40c
45a
45b
45c
Calciodinellum albatrosianum
20,1
18,3
35,1
0,0
0,0
0,0
Calciodinellum operosum
0,0
0,0
11,7
0,0
0,0
0,0
Gonyaulax group
20,1
0,0
0,0
0,0
0,0
59,6
Gymnodinium sp.1
20,1
9,2
0,0
0,0
22,2
0,0
Lingulodinium polyedrum
40,2
0,0
0,0
0,0
0,0
0,0
Melodomuncula berlinensis
40,2
0,0
0,0
0,0
0,0
0,0
Oblea rotunda
0,0
0,0
11,7
0,0
0,0
0,0
Pentapharsodinium dalei type 1
20,1
0,0
0,0
0,0
11,1
0,0
Pentapharsodinium tyrrhenicum type 1
40,2
18,3
23,4
0,0
11,1
0,0
Protoperidinium sp.1
0,0
9,2
0,0
0,0
0,0
0,0
Protoperidinium sp.5
0,0
0,0
11,7
0,0
11,1
0,0
Scrippsiella ramonii
0,0
9,2
0,0
0,0
0,0
0,0
Scrippsiella trochoidea rough type
40,2
18,3
46,8
0,0
0,0
0,0
Scrippsiella trochoidea smooth type
0,0
9,2
11,7
0,0
11,1
0,0
Scrippsiella trochoidea medium type
181,0
73,3
105,4
173,1
111,1
238,4
Scrippsiella trochoidea small type
80,5
64,2
58,5
230,8
0,0
0,0
Scrippsiella sp.1
20,1
0,0
11,7
0,0
11,1
0,0
Scrippsiella sp.4
0,0
9,2
0,0
0,0
0,0
0,0
Thoracosphaera sp.1
0,0
0,0
11,7
0,0
11,1
0,0
Dinophyta sp.2
0,0
0,0
23,4
0,0
0,0
0,0
Dinophyta sp.17
0,0
18,3
0,0
0,0
0,0
0,0
Dinophyta sp.26
0,0
18,3
0,0
0,0
0,0
0,0
Dinophyta sp.33
0,0
0,0
0,0
0,0
11,1
0,0
Codonellopsis schabii
1,0
0,0
0,9
0,6
0,3
0,5
Stenosemella ventricosa
0,1
0,0
0,0
0,0
0,0
0,0
Strobilidium sp. Strombidium acutum
0,1 0,0
0,0 0,0
0,1 0,0
0,0 0,0
0,0 11,1
0,0 0,0
Tintinnopsis cylindrica
0,0
0,0
0,0
0,0
0,1
0,1
Undella claparedei Brachionus plicatilis
0,1
0,0
0,1
0,0
0,0
0,0
0,2
0,0
0,1
0,3
0,0
0,1
Synchaeta sp spiny type
0,3
0,2
0,0
0,2
0,0
0,1
Penilia avirostris Acartia clausi/margalefi
0,0
0,0
0,1
0,0
0,0
0,0
1,0
0,3
0,7
1,5
0,3
0,8
Acartia sp.1
0,1
0,0
0,1
0,0
0,0
0,0
Centropages sp.
0,3 0,0
0,2 0,0
0,0 0,0
0,2 57,7
0,1 0,0
0,2 0,0
Cyst type 1
Figure 3. nMDS plot of surface sediment samples collected at Station 40 and Station 45 in Vlora Bay. Hierarchical clustering has been superimposed with a cut at 60% of similarity
The nMDS ordination (Figure 5, stress = 0.12) with superimposed the hierarchical cluster with a cut at 70% of similarity, showed a sharp separation between the samples of Station 45 (which segregates in a cluster together with the sample 40 1st cm) and the others. The other samples from Station 40 segregate in different clusters, sign of a greater variability at this site. Assemblage structure differed significantly between the two stations across all cm (ANOSIM R=0.655; p=0.001) showing 59% of dissimilarity (SIMPER, Table 5).
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Codonellopsis schabii, Synchaeta sp. and Acartia clausi/margalefi cysts were continuously observed along the whole core layers both at Station 40 and 45. The ciliate was the most abundant species, with a maximum of 342 Âą192 cysts 100g -1 at the 2nd cm of Station 40.
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Figure 4. Resting stage densities and Shannon’s index values recorded for each cm layer along the sediment cores collected at the two investigated stations in Gulf of Vlora (Albania)
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Germination experiments All viable dinoflagellate cyst types observed were isolated and incubated under controlled conditions to obtain germination. Generally a successful excystment allowed us to confirm the cyst-based identification, but in some cases it was possible to discriminate among cysts sharing similar morphology. Alexandrium minutum and Scrippsiella sp.1, have a round cyst, with a clear and smooth wall with mucous material attached, while Protoperidinium thorianum and Protoperidinium sp.1 cysts are round-brown and smooth. Finally, Gymnodinium nolleri and Scrippsiella sp.4 produce round-brown cysts with a red spot inside. The germination of all these cyst types allowed us to identify cryptic features in their morphology and/or structure leading to a correct identification.
Table 4. Results of the SIMPER analysis for resting stages from surface sediments at Station 40 and 45 in Gulf of Vlora. Station 40 Averagesimilarity: 56,81 Taxa Scrippsiellatrochoidea medium type Scrippsiellatrochoidea small type Scrippsiellatrochoidearoughtype Pentapharsodiniumtyrrhenicumtype 1 Calciodinellumalbatrosianum
Av.Abund 119,92 67,73 35,13 27,33 24,53
Av.Sim 21,61 15,81 6,44 5,18 4,94
Sim/SD 7,45 6,14 2,78 8,96 7,24
Contrib% 38,05 27,83 11,34 9,13 8,69
Cum.% 38,05 65,87 77,21 86,34 95,03
Station 45 Averagesimilarity: 40,37 Taxa Scrippsiellatrochoidea medium type
Av.Abund 174,21
Av.Sim 40,03
Sim/SD 5,87
Contrib% 99,16
Cum.% 99,16
Stations 40 & 45 Averagedissimilarity = 58,20 Table 5. Results of the SIMPER analysis for resting stages along the sediment cores collected at Station 40 and 45 in Gulf of Vlora
Figure 5. nMDS plot of samples from each cm of the sediment cores collected at Station 40 and Station 45 in Vlora Bay. Hierarchical clustering has been superimposed with a cut at 70% of similarity
Cysts ascribed to the paleontological taxa Bicarinellum tricarinelloides and Calciperidinium asymmetricum germinated confirming they belong to modern taxa. The active stages obtained were tentatively identified as scrippsielloid dinoflagellates. An unknown ciliate cyst, with a papula at both extremities, produced an active stage identifiable as belonging to the genus Strombidium (Figure 2). Table 3. Abundance and diversity indexes calculated for resting stages in surface sediments at the two stations investigated in Gulf of Vlora. Abundance: the average ± standard deviation from the three replicates. Total density: the total of cysts observed in the three replicates from each station. S: the number of taxa identified (average ± standard deviation). d: Margalef diversity index. H’: Shannon diversity index. J’: Pielou equitability index. abundance
total density
S
d
H’
J’
Station 40
389±127
1167
18±2.7
2.9±0.3
2.2±0.1
0.7±0.1
Station 45
329±123
987
11±4.4
1.8±0.9
0.5±0.2
0.5±0.2
cysts g-1 dw
cysts g-1 dw
Proceedings
Station 40 Averagesimilarity: 44,16 Taxa Centropagessp. Codonellopsisschabii Acartiaclausi/margalefi Synchaetasp. Spinytype Peniliaavirostris Brachionusplicatilis Stenosemella ventricosa Strobilidiumsp. Scrippsiellaspp. Gonyaulaxspp. Strombidiumconicum
Av.Abund 1,77 2,10 1,56 1,47 1,14 0,96 0,78 0,73 0,57 0,54 0,44
Av.Sim 8,77 7,00 6,21 5,31 4,47 2,90 1,47 1,43 0,95 0,71 0,69
Sim/SD 0,86 1,31 1,22 1,10 0,98 0,81 0,55 0,51 0,36 0,34 0,33
Contrib% 19,86 15,86 14,06 12,02 10,13 6,56 3,32 3,23 2,14 1,60 1,57
Cum.% 19,86 35,72 49,78 61,81 71,93 78,49 81,81 85,04 87,18 88,79 90,36
Station 45 Averagesimilarity: 52,61 Taxa Acartiaclausi/margalefi Synchaetasp. Spinytype Codonellopsisschabii Strobilidiumsp. Centropagessp. Brachionusplicatilis Acartia sp.1 Lingulodiniumpolyedrum
Av.Abund 1,88 1,73 1,43 1,12 1,20 0,84 0,75 0,74
Av.Sim 12,13 10,91 6,73 6,05 6,05 2,73 2,57 2,39
Sim/SD 2,08 1,59 1,12 0,92 1,02 0,63 0,58 0,59
Contrib% 23,05 20,74 12,80 11,51 11,50 5,19 4,89 4,54
Cum.% 23,05 43,79 56,59 68,10 79,60 84,79 89,67 94,22
Groups 40 & 45 Averagedissimilarity = 58,63
Discussion The total number of resting stages recognized in the present study is particularly high, if compared with other studies in the same geographic area. None of the preceeding studies gave a number higher than that here reported, notwithstanding the consideration of a largest geographic area (the whole North Adriatic, in Rubino et al., 2000), a highest number of samples (157 sediment samples in Moscatello et al., 2004), or a closest geographic position (the Albanian gulf of Drin, in Rubino et al., 2009). This result is perhaps due to our enhanced ability, 43
44
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with time, to identify cysts from different species, but such a result could depend on the consideration of different depths into the sediments. In fact the other mentioned studies reported only cysts from the sediment surface, while in the present case the type list grew of more than 60% with the addition of cysts buried into the sediments. It has to be noted, however, that the Albanian marine sediments have been already ascertained as the richest in cyst content if compared with the Italian ones (Rubino et al., 2009). The reported list, as a consequence of its richness, adds 42 morphotypes to the Albanian list, and 13 alternative morphotypes to already known taxa. This clearly demonstrates that the description of cyst assemblages in coastal Mediterranean areas, are still far to be exaustive. The finding of high differences in comparison with plankton composition is partially due to the use, among cysts studies, of a terminology derived from paleontological studies which still waits to be uniformed after a comparison with the modern terminology. However, at least for some taxa, it has been well evident how the active stages in the water column assemblages of the Vlora bay (Moscatello et al., 2011) differed in numbers and quality from those reported from the bottom sediments in the present study. Just to give an example, and only considering the surface sediment layer (i.e. the most affected by recent sink and/or resuspension), 4 different species of Scrippsiella (Dinophyta) have been isolated as cysts, but only 2 have been reported as active stages in the water column from the whole bay. Moreover, in this study 5 different cyst types of S. trochoidea were identified, differing by size and wall covering. This is an evidence of great intraspecific diversity buti t could be also a sign of the presence of cryptic species, as discussed by Montresor et al. (2003). The rotifer Synchaeta was not found in the water column, but its resting eggs were well recognizable in the sediments. If the first case confirms that still more is to be known about the morphological variability of cysts produced by the same species (see Rochon et al., 2009 for Dinophyta; or Belmonte, 1992, for Calanoida), the second is an evident case of a species not detected in the active plankton assemblage but waiting in the sediments for a favourable moment to stay in the water column. Among the novelties, it deserves attention the first report of a Ciliophora cyst with two, opposite, papulae (Figure 2) which has never been reported before.
Scrippsiella species. All of them have active cells very difficult to be distinguished, while their cysts differ for the type of calcareous covering or the colour or the presence of spines (Gottschling et al., 2005; Gu et al., 2008). A special mention deserves the recovering during the present study of dinoflagellate cysts whose active stage still waits for an identification. They are still classified with a paleontological name after their description from Pleistocene to Pliocene sediments in the Mediterranean (Versteegh, 1993). Two types (Bicarinellum tricarinelloides and Calciperidinium asymmetricum) germinated producing a dinoflagellate belonging to the family Calciodinellaceae. Anyway their frequent observation in surface sediments also in other Mediterranean areas (Meier & Willems, 2003; Rubino et al., 2010a) and in sediment traps too (Rubino et al., 2010b), is a clear sign that these species actually live in the water column and need to be better investigated.
Vertical distribution into the sediment We are not able to correlate cyst abundance along the sediment cores with the age of deposition, because only a datation of sediment layers could be helpful in this sense. Anyway, our results showed that the total abundance of cysts in the upper layers was up to 10 times greater than in lower layers. At least at Station 40, the sharp decrease of abundance below the 5th cm, is however suggestive of a general crisis of the plankton responsible of that production. The Station 40, due to its position, is a candidate for studies on the history of cyst production (and deposition). In fact, its depth (-54 m) collocates it in a depression of the sea bottom which probably favourishes the sedimentation of fine particles, thus allowing to consider undisturbed their deposition and accumulation. The registered diminution of diversity from lower to upper layers, in addition, could be interpretated as correlated with the growth of cultural eutrophication like in the Tokio bay (Matsuoka, 1999) and the Daja bay (Wang et al., 2004). Germination experiments Incubation of encysted forms under controlled conditions to obtain germination is a useful tool to confirm the identification made with the observation of the cyst, because in some cases, mainly when the cyst morphology is too simple, i.e. spherical, without processes and wall structures, very similar cysts are produced by different species. In the present study, in particular, we observed many dinoflagellate cysts with the same basic morphology, i.e. round body, smooth and brown wall without apparent signs of paratabulation and spines or processes. Their germination allowed us to split this basic type into six species at least. Round-brown cysts are typical of Protoperidinium species (Harland, 1982; Lewis et al., 1984), but we recognized also Diplopsalis lenticula, Gymnodinium nolleri and Oblea rotunda, besides three Protoperidinium species. In the same way, it was possible to distinguish between Alexandrium minutum and Scrippsiella sp.1, even if their cysts are very similar but with little differences recognizable only after germination. But also the analysis of the cysts allows the identification of species whose active stages are indistinguishable, under the optical microscope, at least. This is the case in this study for the Proceedings
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References Belmonte, G. (1992). Diapause egg production in Acartia (Paracartia) latisetosa (Crustacea, Copepoda, Calanoida). Bollettino di Zoologia. (59): 363-366. Belmonte, G., Castello, P., Piccinni, M.R., Quarta, S., Rubino, F., Geraci, S., Boero, F. (1995). Resting stages in marine sediments off the Italian coast. In “Biology and ecology of shallow coastal waters” (A. Elefteriou, et al. eds). Olsen & Olsen Publ., Fredensborg.: 53-58. Belmonte, G., Miglietta, A., Rubino, F., Boero, F. (1997). Morphological convergence of resting stages produced by planktonic organisms: a review. Hydrobiologia. (335): 159-165. Belmonte, G., Pirandola, P., Degetto, S., Boero, F. (1999). Abbondanza, Vitalità e distribuzione verticale di forme di resistenza nei sedimenti del Nord Adriatico. Biologia Marina Mediterranea. (6): 172-178. Boero, F., Belmonte, G., Fanelli, G., Piraino, S., Rubino, F. (1996). The continuity of living matter and the discontinuities of its constituents: do plankton and benthos really exist? Trends in Ecology and Evolution. (11): 177-180. Dahms, H.-U., Li, X., Zhang, G., Quian, P.-Y. (2006). Resting stages of Tortanus forcipatus (Crustacea, Calanoida) in sediments of Victoria Harbour, Hong Kong. Estuarine Coastal and Shelf Sciences. (67): 562-568. Giangrande, A., Geraci, S., Belmonte, G. (1994). Life-cycle and life-history diversity in marine invertebrates and the implications in community dynamics. Oceanography Marine Biology, Annual Review. (32): 305-333. Gottschling, M., Knop, R., Plotner, J., Kirsch, M., Willems, H., Keupp, H. (2005). A molecular phylogeny of Scrippsiella sensu lato (Calciodinellaceae, Dinophyta) with interpretations on morphology and distribution. European Journal of Phycology. (40): 207-220. Gu, H., Sun, J., Kooistra, W.H.C.F., Zeng, R. (2008). Phylogenetic position and morphology of thecae and cysts of Scrippsiella (Dinophyceae) species in the east China Sea. Journal of Phycology. (44): 478-494. Hairston, N.G.Jr., Van Brunt, R.A., Kearns, C.N., Engstrom, D.R. (1995). Age and survivorship of diapausing eggs in a sediment egg bank. Ecology. (76): 1706-1711. Harland, R. (1982). A review of recent and quaternary organic-walled dinoflagellate cysts of the genus Protoperidinium. Paleontology. (25): 369-397. Jiang, X., Wang, G., Li, S. (2004). Age, distribution and abundance of viable resting eggs of Acartia pacifica (Copepoda: Calanoida) in Xiamen Bay, China. Journal of Experimental Biology and Ecology. (312): 89-100. Lewis, J., Dodge, J.D., Tett, P. (1984). Cyst-theca relationship in some Protoperidinium species (Peridiniales) from Scottish sea lochs. Journal of Micropaleontology. (3): 25-34. Maiorano, P., Mastrototaro, F., Beqiraj, S., Costantino, G., Kashta, L., Gherardi, M., Sion, L., D’Ambrosio, P., Carlucci, R., D’Onghia, G., Tursi, A. (2011). Biological study of the benthic communities on the soft bottom of the Vlora Gulf (Albania). Journal of Coastal Research. (58): 95-105. Marcus, N.H., Boero, F. (1998). Production and plankton community dynamics in coastal aquatic systems: the importance of benthic pelagic coupling in the forgotten role of life cycles. Limnology and Oceanography. (43): 763-768. 46
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Marcus, N.H., Lutz, R., Burnett, W., Cable, P. (1994). Age, viability and vertical distribution of zooplankton resting eggs from an anoxic basin: evidence of an egg bank. Limnology and Oceanography. (39): 154-158.
MESOZOOPLANKTON COMPOSITION AND VARIABILITY IN THE GULF OF VLORA (ALBANIA)
Matsuoka, K. (1999). Eutrophication process recorded in dinoflagellate cyst assemblage – a case of Yokohama port, Tokyo Bay, Japan. Science of the Total Environment. (231): 17-35.
1
Salvatore Moscatello, 2Edmond Hajdëri, 1Francesco Denitto, 3M. Licciano, 1 Irene Vaglio, *1Genuario Belmonte
Meier, K.J.S., Willems, H. (2003). Calcareous dinoflagellate cysts in surface sediments from the Mediterranean Sea: distribution patterns and influence of main environmental gradients. Marine Micropaleontology. (48): 321-354.
1
Lab. of Zoogeography and Fauna, CoNISMa U.O. Lecce, DiSTeBA University of the Salento, 73100 Lecce, Italy. 2 Kompleski Spitalor Universitar "Zoja e Keshillmit Te Mire", Rruga e Durresit, Tirane, Albania. 3 Lab. of Systematic Zoology, CoNISMa U.O. Lecce, DiSTeBA University of the Salento, 73100 Lecce, Italy. * E-mail genuario.belmonte@unisalento.it
Montresor, M., Sgrosso, S., Procaccini, G., Kooistra, W.H.C.F. (2003). Intraspecific diversity in Scrippsiella trochoidea (Dinophyceae): evidence for cryptic species. Phycologia. (42): 56-70. Moscatello, S., Rubino, F., Saracino, O.D., Belmonte, G., Boero, F. (2004). Plankton biodiversity around the Salento Pensinsula (South East Italy): an integrated water/sediment approach. Scientia Marina. (68): 85-102. Moscatello, S., Caroppo C., Hajderi E., Belmonte, G. (2011). Space Distribution of Phyto- and Microzooplankton in the Vlora Bay (Southern Albania, Mediterranean Sea). Journal of Coastal Research. (58): 80-94. Onbè, T. (1978). Sugar flotation method for sorting the resting eggs of marine cladocerans and copepods fron sea bottom sediments. Bulletin of the Japanese Society of Scientific Fisheries. (44): 1411. Ribeiro, S., Berge, T., Lundholm, N., Andersen, T.J., Abrantes, F., Ellegaard, M. (2011). Phytoplankton growth after a century of dormancy illuminates past resilience to catastrophic darkness. Nature Communications. (2): 311-317. Rochon, A., Lewis, J., Ellegaard, M., Harding, J.C. (2009). The Gonyaulax spinifera (Dinophyceae) “complex”: Perpetuating the paradox? Review of Palaeobotany and Palynology. (155): 52-60. Rubino, F., Saracino, O.D., Fanelli, G., Belmonte, G., Miglietta, A.M., Boero, F. (1998). Life cycles and pelago-benthos interactions. Biologia Marina Mediterranea. (5): 253-259. Rubino, F., Belmonte, G., Miglietta, A.M., Geraci, S., Boero, F. (2000). Resting stages of plankton in recent North Adriatic sediments. Marine Ecology. (21): 263-284.
Abstract Mesozooplankton was collected during two cruises in the Bay of Vlora (Albania), in May 2007 and January 2008, respectively. A total of 64 samples were analysed, from 16 sampling points. A total of 198 categories of mesozooplankton were recognized, and 62 of them were not shared by both periods. The present study offers the first detailed faunal list for a coastal site in Albania, and the record of some rare species the Mediterranean Sea (the trachymedusa Geryona, and the hydromedusa Bouganvillia). A progressive growth of the confinement grade has been evidenced passing from the external stations to the most internal ones. The internal area of the Bay was characterized by high abundances of individuals corresponding to a relatively low number of species if compared with the outer stations. The space characterization of the Bay was clearer than those derived from a similar study conducted on micro and phytoplankton. The two seasons appeared sharply separated, and a gradient was evident from inner stations and outer ones in each period, being all the others in the middle. Due to ecological indicators and to the population numbers, a high degree of confinement has not been recognized even in the inner stations. This is probably due to the large water volume present in the Bay (maximum depth, 54 m) which impedes the stressing action of daily condition-variability typical of confined coastal areas. Such a high level of stability, coupled with the relatively high biodiversity encountered, encourages actions of protection for the Bay of Vlora.
Rubino, F., Saracino, O.D., Moscatello, S., Belmonte, G. (2009). An integrated water/sediment approach to study plankton (a case study in the southern Adriatic Sea). Journal of Marine Systems. (78): 536546.
Keywords: Mesozooplankton, Gulf of Vlore, South-East Europe, Mediterranean Sea, Biodiversity, Seasonality, Space distribution.
Rubino, F., Belmonte, M., Caroppo, C., Giacobbe, M.G. (2010a). Dinoflagellate resting stages from surface sediments of Syracuse Bay (Western Ionian Sea, Mediterranean). Deep Sea Research II. (57): 243-247.
Introduction
Rubino, F., Monchev, S., Belmonte, M., Slabakova, N., Kamburska, L. (2010b). Resting stages produced by plankton in the Black Sea – Biodiversity and ecological perspective. Rapp. Comm. Int. Mer Médit. (39): 399. Versteegh, G.J.M. (1993). New Pliocene and Pleistocene calcareous dinoflagellate cysts from southern Italy and Crete. Review of Palaeobotany and Palynology. (78): 353-380. Wang, Z., Matsuoka, K., Qi, Y., Chen, J., Lu S. (2004). Dinoflagellate cyst records in recent sediments from Daya Bay, South China Sea. Phycological Research. (52): 396-407.
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Coastal marine environments (transitional waters, harbours, marine bays), are characterized by a high variability if compared with open sea ones (Amanieu & Lasserre, 1982; Badosa et al., 2007; Elliott & Quintino, 2007). A significant decrease in species richness and a progressive demographic increase of populations is observed in the zooplankton concurrently with the increase of the confinement grade. In comparison with the open sea, an additional rule also wants a reduction of the body size of specimens in confined waters (Blackburn & Gaston, 1994; Uye, 1994; Belmonte & Cavallo, 1997). The environmental variability is probably the cause of a shortage of life cycles, furthermore they can be interrupted with production of resting stages in many species (Giangrande et al., 1994; Rubino et al., 1998; Moscatello & Belmonte, 2004). Zooplankton of Mediterranean bays are among the best studied of the world seas. It contains abundant and well reliable indicators of the season and of the confinement grade (sensu Guelorget & Perthuisot, 1992). In general, the zooplankton of Mediterranean bays is assimilated with that of brackish/confined waters: it shows biomass peaks one or more times in the period from the Spring to the Autumn, mainly due to small-sized individuals and/or species in the warmest months (Calbet et al., 2001; Lam-Hoai & Rougier, 2001). Apart for meroplankton components, generally seasonal and well represented in coastal areas all over the world, among the holoplankton the copepods of the family Acartiidae are typically considered as indicators of the most coastal, sheltered areas (Razouls, 1995). The Gulf of Vlora, a bay in the center of the Mediterranean Region, is considered as affected by Levantine surface currents which should maintain it sensibly different from the front faced Italian coast of the Otranto Channel, affected by Northerly Adriatic surface currents (Robinson et al., 2001). The Gulf of Vlora is probably one of the less studied bays of all the Mediterranean Sea. The poorness of the economy in the last 40 years, the presence of one side, the Karaburun 48
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peninsula, completely deprived of human settlements, and the forbidden use of any kind of motor ships and rubber boats in the last 6 years, allowed the re-storing of a nearly pristine situation without equals in the rest of the Mediterranean Bays. The entire coastal environment of Albania is one of the less studied of the Mediterranean. Although Italy showed cultural and political interest on Albania at the beginning of the XX century, studies of the recent oceanographic Italian community did not produce reliable data. Cruises II and VII of the Austro-Italian expedition (1909-1911) produced a total list of 58 copepod species for Albanian waters (Grandori, 1913). In the second half of the XX century, only studies on adjacent areas can be used as a comparison. Hure and Scotto di Carlo (1968) considering a South Dalmatian bay, represented a good reference point to compare the copepod fauna of relatively limited areas (the Gulf of Naples, in the Tyrrhenian Sea, with the coastal South Adriatic of the former Yugoslavia). The study reported a list of 145 copepod species and still represents a reference for the geographic area (South Adriatic Sea). The first study concerning the entire zooplankton assemblage, in bays of the South Adriatic (however not Albanian), was produced by Gamulin (1979) on samples collected from 1947 to 1952. The zooplankton of the Dubrovnik bay of that study listed 149 taxa of 15 different Phyla. Successively, Regner (1985) with a 5 year program of sample collection, ascertained the presence of 53 copepod species in the Kastela bay (South Dalmatia) zooplankton, each date being characterized by 9 to 21 species (corresponding to summer and winter respectively). Of the total species, only 25 were not found in all the 5 years studied, thus testifying the high structural variability of that community. In the study of Lucic and Onofri (1990), Maliston Bay (Dalmatia) resulted heavily dominated by copepods (upto 90% of total numbers) assorted according 37 different species. Studies conducted in the Italian part of the south Adriatic Sea reported a well diversified mesozooplankton community. Detailed seasonal and space investigations on zooplankton biomass distribution and composition (Marano, et al., 1989; Hajdëri & Casavola, 2001) and the quanti-qualitative seasonal distribution of Cladocera (Hajdëri et al., 1993) and Copepods (Hajdëri, 1998) communities were undertaken in coastal and open epipelagic waters of the South Adriatic Sea. The Copepod community resulted similar to that of Eastern Mediterranean waters. Among the 93 Copepod species found, 11 were reported for the first time in the Adriatic Sea. An evident decline of population abundance was observed in the coastal-open waters direction between 100 and 200 m bathymetries and from northern to southern transects. On the contrary, the species abundance and the community diversity increased from north to south and in coastal-open waters direction. Of a certain interest can be considered the situation of the Otranto Channel where 64 Copepod species were reported during a whole year (Hajdëri et al., 1994), and the increase of copepod diversity and of zooplankton biomass was observed in the coastal-open water direction. Relevant seasonal differences in the community composition were found, due to the variability of the hydrological features. In Bari coastal waters (Italian South Adriatic), just out of the harbour, a rich zooplankton community (if compared with those of north and central Adriatic) has been reported (Hajdëri & Marano, 1998) dominated by Copepods (34 species representing the 63% of total individuals) with both coastal and neritic species. Further indications on the composition of bay zooplankton in the Central Mediterranean Sea, could be derived from the study of Belmonte et al., (2001) carried out in the Taranto Sea system (Northern Ionian Sea). Ecological characteristics deriving by this study confirm that the number of taxa and their medium body sizes decrease with the increase of the confinement grade. On the contrary, the number of individuals and the demographic variability increase in accordance with the confinement grade. An attempt to study the zooplankton of the Gulf of Vlore has been just proposed as a test by Moscatello and Belmonte (2006) for the elaboration of a sampling plan which was successively elaborated for the present work. Successively, a study on the phyto and micro-zooplankton of the Gulf of Vlore has been realized by Belmonte et al. (2011) which could represent a reference point for the discussion of the seasonality and the space distribution of the plankton community based on the data here presented. Anyhow, the present is the first detailed report on the mesozooplankton community of the Vlora bay.
Proceedings
49
Material and methods Meso-zooplankton was collected during two 7-days scientific cruises conducted in the Gulf of Vlora (Albania) with the oceanographic ship Universitatis (CoNISMa), in May-June (Spring) 2007 and January (Winter) 2008 respectively. Samples were collected at 18 different stations arranged according 4 W-E transects (A, B, C, D) in the Gulf of Vlora, and one N-S transect (G) in the mezocanal (Figure 1). Stations have been selected to obtain at least 3 sampling stations within each of the 4 areas that a preliminary study (Moscatello and Belmonte, 2006) proposed to be present in the Gulf. Samples were collected with a plankton net WP2 (mouth diameter, 54 cm) towed obliquely from the bottom up to the surface, at each station. A flow-metre positioned at the net mouth allowed to measure the water volume which passed throughout the net at each sample collection. Each sample was the result of a water filtration ranging from 0.5 to 13.1 m3 (see Table 1). To avoid errors due to the sunlight affection on the vertical distribution of plankton in the water column, each day the sampling has been conducted from the sunset (6.30 p.m. in Spring; 4.00 p.m. in Winter) onward. To allow a reliable statistical analysis of data, in each station two samples (replicates) have been collected. All the zooplankton samples were fixed in situ with 1.6% formaldehyde solution in original sea water.
Figure 1. Map showing the position of the 18 sampling stations aligned along 5 transects (A, B, C, D, G) in the Gulf of Vlore. Station D5 was not sampled in May 2007, and Station B3 was not sampled in January 2008.
50
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Table 1. Bay of Vlora, list of the sampling stations, with the main characteristics relative to the two sampling periods. station
date
A1
A2
A3
B1
5/26/2007
latitude Nord 40°19'657
longitude East 19°25'864
1/21/2008
40°19'822
19°25'824
5/26/2007
40°19'999
19°27'051
1/21/2008
40°19'833
19°27'056
5/26/2007
40°20'801
19°27'935
1/21/2008
40°20'766
19°28'227
5/28/2007
40°21'527
19°24'998
1/21/2008
40°21'552
19°25'003
5/28/2007
40°21'823
19°26'371
1/21/2008
40°21'821
19°26'332
B3
5/31/2007
40°22'014
19°27'362
B4
\ 5/28/2007
\ 40°22'283
\ 19°28'472
1/21/2008
40°22'208
19°28'416
5/28/2007
40°23'735
19°24'934
1/20/2008
40°23'815
19°24'884
5/29/2007
40°24'053
19°26'016
1/20/2008
40°24'005
19°25'994
5/28/2007
40°24'400
19°27'245
1/20/2008
40°24'355
19°27'144
5/29/2007
40°25'280
19°21'926
1/19/2008
40°25'282
19°22'014
5/29/2007
40°25'798
19°23'391
1/19/2008
40°25'732
19°23'241
5/29/2007
40°26'050
19°24'606
B2
C2
C3
C4
D1
D2
D3
depth m 1.00 23.00 1.00 32.00 1.00 24.00 1.00 15.00 1.00 31.00 1.00 15.00 1.00 51.80 1.00 52.00 1.00 51.92 1.00 52.00 1.00 46.00 \ 1.00 13.44 1.00 16.00 1.00 53.00 1.00 53.00 1.00 54.07 1.00 54.00
temper. °C 22.57 18.19 14.68 14.55 23.73 17.42 14.38 14.48 23.37 15.54 14.57 14.51 19.72 15.03 14.72 13.98 20.19 15.02 14.38 13.99 20.46 15.07 \ 22.20 18.92 14.22 14.41 20.39 14.90 14.09 10.01 20.91 15.00 14.06 14.07
salinity ppt 37.23 38.12 38.34 38.34 36.40 37.90 38.19 38.33 37.10 38.26 38.22 38.32 37.98 38.42 38.38 38.25 37.99 38.43 38.28 38.25 37.72 38.40 \ 37.35 38.02 38.13 38.30 37.90 38.45 38.23 38.26 37.90 38.44 38.24 38.27
diss.O2 ppt 7.15 7.67 7.70 7.64 6.80 7.54 7.72 7.70 6.80 7.57 7.71 7.68 8.60 6.97 7.60 7.45 8.50 6.84 7.86 7.51 6.80 6.73 \ 6.94 7.78 7.76 7.72 6.90 7.05 7.74 7.55 6.80 6.85 7.70 7.65
1.00 53.02 1.00 53.00 1.00 46.00 1.00 46.00 1.00 44.88 1.00 45.00 1.00
20.77 15.01 14.04 14.05 20.73 15.01 14.90 14.06 21.15 15.19 14.38 14.05 21.25
37.70 38.36 38.15 38.26 37.00 38.42 38.40 38.26 37.32 38.31 38.31 38.26 37.58
6.90 7.11 7.72 7.64 7.60 6.90 7.57 7.58 4.50 7.27 7.69 7.62 6.83
Proceedings
filtered vol. cube m 0,5-0,9
1/19/2008
40°26'039
19°24'578
5/29/2007
40°26'615
19°26'097
1/19/2008
40°26'630
19°26'010
D5
\ 1/19/2008
\ 40°27'139
\ 19°27'525
G1
5/30/2007
40°26'567
19°18'156
1/20/2008
40°26'479
19°18'281
5/30/2007
40°26'616
19°17'632
1/20/2008
40°26'990
19°18'009
5/30/2007
40°27'357
19°19'044
1/20/2008
40°27'597
19°18'759
D4
4,2-5,0 0,2-0,8 2,5-3,4 3,5-9,6
G2 1,2-1,6 7,6-9,2 G3 6,3-9,5 9,1-10,2
44.66 1.00 45.00 1.00 41.00 1.00 42.00 \ 1.00 24.70 1.00 60.00 1.00 60.00 1.00 50.00 1.00 51.00 1.00 33.00 1.00 49.00
15.50 14.23 14.14 21.13 16.10 13.91 14.09 \ 13.91 13.95 21.01 15.02 15.17 14.30 20.90 15.15 15.25 14.76 21.17 15.33 15.26 14.84
38.30 38.28 38.29 37.69 38.27 38.16 38.27 \ 38.08 38.21 37.86 38.44 38.44 38.30 37.95 38.45 38.44 38.40 37.65 38.35 38.43 38.41
7.53 7.72 7.67 6.72 7.58 7.78 7.68 \ 7.84 7.17 6.77 7.23 7.46 7.58 6.77 7.29 7.50 7.55 6.73 7.25 7.54 7.52
2,6-5,4 6,7-7,8 4,2-9,6 \ 4,3-5,4 8,5-9,6 4,7-7,0 6,4-9,3 4,1-6,0 3,4-4,5 9,1-10,6
At each station, a vertical profile of temperature and salinity of the water has been obtained by a multiparametric probe (see data in Mangoni et al., 2011). In the laboratory, samples were analysed under a compound microscope at 50x magnification. Three aliquots of 8-10 cc of well mixed samples were analysed to count specimens according to taxa and/or developmental categories (larvae and juvenes were often not classifiable at the species level as the adults). The remaining part of each sample has been analysed to search rare species and to check numerical data of less abundant categories. Data were presented as number of individuals per cube metre (indiv. m-3) A particular attention has been dedicated to the taxa identification due to the fact that the present collection is the first one which describes the zooplankton of the Gulf of Vlora. In detail, Copepoda (adults, nauplii, and juvenes), Hydrozoa (medusae), and Polychaeta (mostly larvae) have been recognized at the lowest taxonomic level possible, allowing the proposal for the creation of a check list of zooplankton species of the Albanian marine fauna. The differences in meso-zooplankton abundance, species richness (Margalef), and diversity (Pielou’s evenness), among sampling stations were tested by a univariate analysis of diversity indices routine in PRIMER (Plymouth Routines In Multivariate Ecological Research) version 6β R6 (PRIMER-E) (Clarke & Warwick, 1994). The significance of both temporal and spatial variation of meso-zooplankton composition was tested using a Two-Way crossed Analysis of Similarities for replicated data (ANOSIM2) routine in PRIMER version 6β R6 (PRIMER-E) (Clarke & Warwick, 1994). “Transect” and “Season” were considered as fixed orthogonal factors. For multivariate analyses, only 113 taxa have been considered (those who were quickly recognizable at the microscope and did not slow the count procedure). Stations B3 and D5 were sampled in only one period (May 2007 and January 2008, respectively). Their data were used for the composition of the faunal list, but not for the multivariate analysis. Data have been organized in a 113 (variables, taxa) x 32 (16 x 2 sampling stations) matrix. The absolute abundance of each taxon was fourth root transformed, to severely down-weight the importance of numerically dominant species. The method of non-parametric ordering (MDS) applied to the matrix of similarities allowed to graphically describe the differences in the community structure defined among different transects and over time. Stress value were shown for obtained MDS plots to indicate the goodness of representation of differences among samples (Clarke, 1993). A “Two-Way” similarity percentage procedure (PRIMER SIMPER routine, Clarke, 1993) was used
5,9-10,4 5,9-8,0 \ 1,7-2,2 1,0-1,9 9,9-12,7 6,7-10,6 7,5-10,0 7,1-9,3 11,013,1 6,7-10,6 7,4-9,9 3,6-4,9 6,1-7,7 6,3-7,7 6,9-8,8 51
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Oral presentations: Biodiversity and ecosystem functioning
International Conference MarCoastEcos2012, Tirana, Albania, 25-28 April 2012
in order to obtain the percentage contribution that each taxon provided to Bray-Curtis similarities measures. A cut-off criterion was applied to allow the identification of the subset of species whose cumulative percentage contribution reached 40% of the similarity value.
Results – Abiotic features For a detail on the abiotic features of the bay, we refer directly to Mangoni et al., (2011), who worked onboard with us during the same cruises. Table 1 shows just the values at the extremities of the water column (bottom and surface) at each station. It is evident how the East side of the bay is affected by freshwater inputs (stratified on the surface) more than the West side (see Salinity values). As regarding the temperature, the water column was clearly stratified in Spring 2007 with up to 7°C of difference among bottom and surface values. This stratification was completely absent in Winter 2008. – Zooplankton A total of 64 samples were collected during the two cruises (Spring 2007, Winter 2008) at 16 sampling stations (D5 was not interested by May cruise, B3 was not interested by January cruise). A total of 198 categories of mesozooplankton were recognized (104 at level of genus or species). The most representative taxa were Copepoda (101 categories, 74 at the genusspecies level, on a total of 124 Crustacea), Cnidaria (23 categories), and Polychaeta (19). The species composition revealed the presence of some rare elements for the Mediterranean fauna, as the trachymedusa Geryonia sp. (Fig. 2a) and the hydromedusa Buganvillea nana, a species which has been recently described by Denitto et al., (2007) from the Salento peninsula (South East Italy) (Figure 2b). The two periods under study shared 136 categories of the 198 recorded. The 62 unshared categories were divided in 21 exclusive of May 2007, and 41 exclusive of January 2008. Only 10 categories were ubiquitous being present at all the stations in both the periods. Among these 10 categories, apart 8 which were of high level taxa (hence heterogeneously composed), only 2 species were ubiquitous of both periods: Oikopleura sp. (Larvacea) and Farranula rostrata (Corycaeidae) (Table 2). From the abundances point of view (Table 3), station A2 and D5 were the richest (33,073 indiv m-3, Spring 2007, and 19,651 indiv m-3, Winter 2008, respectively,) mainly due to the dominance of Calanoida Copepoda (Acartia, Clausocalanus and Paracalanus genera). The jelly plankton was represented by Siphonophora and Appendicularia.
a
b
Figure 2. a) Geryonia sp. and detail of the capsule and dardo of a neurythelic macrobasic nematocyst easily detectable in clusters on tentacles which appear moniliform. Bar, 1 mm. (drawing of F. Denitto). b) Bougainvillia nana adult. (redrawn from Denitto et al., 2007).
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Table 2. Bay of Vlora, list of the meso-zooplankton categories found in samples collected in the two periods considered (Spring 2007, and Winter 2008). Numbers indicate, for each period, the presence frequency (number of stations with that taxon) being the number of sampling stations 17 for each period. taxa Noctiluca sp. Globigerina sp. Foraminifera undet. Radiolaria undet. Tintinnina undet. Cnidaria planula Anthomedusae actinula Hydromedusae undet. Obelia sp. Liriope sp. Leptomedusae undet. Clytia sp. Anthomedusae undet. Hydractinia sp. Eutima sp. Bouganvillia nana Geryonia sp. Cunina sp. Dipurena gemmata Janiopsis costata Pandeidae undet. Siphonophora undet. Siphonophora Prayidae Siphonophora Abyliidae Siphonophora Diphyidae Siphonophora Clausophyidae Siphonophora Agalmatidae Scyphozoa ephyra Ctenofora cidippus Ctenofora undet. Nemertea pilidium Nematoda undet. Turbellaria undet. Polyclada Muller larva Polychaeta larva undet. Alciopidae larvae Aphroditidae larvae Chrysopetalidae larvae Goniadidae larvae Hesionidae larvae Ladice sp. Magelona sp. Maldanidae larvae Orbiniidae larvae Oweniidae mitraria Pectinaridae larvae Phylliroe bucefala Phyllodocidae larvae Poecilochaetus sp. Sabellidae larvae Spionidae larva Terebellidae larvae 54
2007 May
2008 Jan
0 16 2 14 11 1 5 5 4 0 0 1 5 1 1 0 0 0 12 1 1 7 6 3 15 0 2 2 13 0 13 2 0 2 3 3 0 0 0 0 0 11 0 1 3 2 0 7 0 5 15 4
1 16 0 17 1 3 3 3 15 13 3 0 8 2 1 2 1 2 0 0 1 5 16 6 16 4 0 0 5 1 13 0 1 2 1 9 1 1 1 1 1 11 10 3 8 0 1 12 1 10 17 5
taxa Harpacticoida copepodid undet. Harpacticoida nauplii undet. Clitemnestra rostrata Euterpina acutifrons Macrosetella sp. Microsetyella-Euterpina nauplii Longipediidae nauplii undet. Microsetella rosea Pachos sp. Sapphirina sp. Scolecitrix bradyi Monstrilloida copepodi undet. Anomalocera sp. Acartiidae copepodid undet. Acartiidae nauplii undet. Acartia clausi Acardtia danae Acartia negligens Acartia margalefi Calanus sp. Calanidae nauplii undet. Calanus helgolandicus Calanoida copepodid undet. Calanoida nauplii undet. Calocalanidae copepodid undet. Calocalanus contractus Calocalanus elongatus Calocalanus pavo Calocalanus plumulosus Calocalanus styliremis Calocalanus tenuis Candaciidae copepodid undet. Candacia ornata Candacia giesbrechti Centropagidae copepodid undet. Centropages kroyeri Centropages ponticus Centropages typicus Clausocalanus copepodi undet. Clausocalanus arcuicornis Clausocalanus furcatus Clausocalanus joboei Clausocalanus lividus Clausocalanus paululus Clausocalanus pergens Ctenocalanus sp. Ctenocalanus vanus Diaixis sp. Eucalanus attenuatus Euchaetidae copepodid undet. Isias clavipes Labidocera wollastoni Proceedings
2007 May
2008 Jan
10 1 12 15 0 1 15 4 0 4 0 1 1 17 5 17 0 4 1 12 14 1 9 1 17 0 0 2 1 13 0 5 0 0 17 17 3 16 17 0 1 3 0 6 1 17 8 14 0 0 17 4
3 9 10 16 1 0 4 7 1 5 1 0 0 16 0 12 2 14 1 10 11 2 13 6 17 3 5 5 3 14 1 12 1 1 5 2 0 11 16 6 13 1 7 15 0 9 5 10 1 2 6 2
Oral presentations: Biodiversity and ecosystem functioning Tomopteridae undet. Foronida actinotrocha Bryozoa cyphonautes Chaetognatha undet. Gastropoda veliger Bivalvia veliger Tecosomata undet. Creseis sp. Echinodermata dipleurula Asteroidea bipinnaria Echinoidea pluteus Ophiuroidea pluteus Holothuroidea auricularia Oikopleura sp. Fritillaria sp. Fritillaria pellucida Ascidiacea larva Thaliacea undet. Branchiostoma lanceolatum Mormonilla sp. Lubbockia squillimana Oithonidae copepodid undet. Oithonidae nauplii Oithona nana Oithona plumifera Oithona similis Oncaeidae copepodid undet. Oncaea dentipes Oncaea media Oncaea mediterranea Oncaea minuta Oncaea obscura Oncaea subtilis Oncaea venusta Copilia quadrata Trichonia sp. Corycaeidae copepodid undet. Corycaeidae nauplius Agetus typicus Agetus flaccus Agetus limbatus Ditrichocorycaeus anglicus Farranula rostrata Onycocorycaeus giesbrechti Onycocorycaeus latus Onycocorycaeus ovalis Urocorycaeus furcifer Cyclopoida undet.
0 11 16 17 17 17 17 1 1 0 11 2 14 17 11 1 0 11 0 0 0 17 11 17 13 17 17 1 12 7 17 2 5 0 5 6 17 2 7 3 2 16 17 7 5 6 3 0
5 10 10 17 17 17 16 1 0 8 13 11 17 17 17 16 3 9 1 1 10 17 9 16 14 16 17 2 16 5 16 7 2 2 4 5 17 2 1 10 0 12 17 4 2 4 4 1
Labidocera-Centropages nauplii Lucicutia flavicornis Mecinocera clausi Mesocalanus tenuicornis Metacalanus sp. Nannocalanus minor Neocalanus robustior Paracalanus aculeatus Paracalanus denudatus Paracalanus nanus Paracalanus parvus Paracalanus copepodid undet. Paracartia latisetosa Pleuromamma gracilis Pontellidae copepodid undet. Pontellidae-Rhincalanidae nauplii Temora stylifera Temora longicornis Temoridae copepod undet. Temoridae nauplii Penilia avirostris Podon polyphemoides Podon leuckartii Evadne nordmanni Evadne spinifera Pseudevadne tergestina Sergestidae elaphocaris Decapoda Brachyura zoea Decapoda Brachyura megalopa Decapoda Anomura zoea Decapoda Natantia zoea Euphausiacea nauplius Euphausiacea zoea Ostracoda undet. Cirripedia balanomorpha nauplius Cirripedia lepadomorpha nauplius Cirripedia cypris Mysidacea undet. Amphipoda Caprellidae undet. Amphipoda Hyperiidae undet. Amphipoda alii Isopoda undet. Nebaliacea undet. Pisces eggs Pisces larva Engraulis egg totale taxa
International Conference MarCoastEcos2012, Tirana, Albania, 25-28 April 2012 9 6 16 2 1 2 0 1 3 9 16 17 1 0 6 11 13 2 3 3 17 16 0 5 15 1 3 16 2 2 16 0 4 11 3 13 1 7 1 1 7 6 1 12 16 6
1 15 16 1 0 2 1 0 5 14 2 17 0 6 2 7 17 0 2 4 14 7 4 0 2 0 6 15 4 0 15 1 8 17 0 1 0 12 1 2 2 10 1 13 16 1
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In Spring 2007 the highest value of species richness (d = 8.942, Margalef index of community diversity) was recorded at station G3 (Mezocanal), whereas the lowest one was at station D3 (d = 5.106). In Winter 2008 the species richness showed values increasing with distance from the inhabited coast: the highest value (d = 6.654) was at D2 station, whereas the lowest one was in C4 station (d = 4.997). The ANOSIM showed overall significant differences among transects (R = 0.327, p < 0.01). The analysis showed highly significant differences among the stations proper of the Gulf (A, B and C) and those in the Mezokanal Strait (transect G). Between the transects A and B and between C and D (see Table 5) there were no significant differences. These patterns are evident from Proceedings
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graphic inspection of MDS plot where it is possible to identify two distinct areas in the Gulf (one internal area - transect A - and one intermediate area where the differences between transects B, C and D are less marked) and one area (transect G), which distinguishes itself evidently for its position closer to the open sea. The ANOSIM showed highly significant differences in the mesozooplankton populations of the two different sampling cruises (R = 0.95, p < 0.001) as illustrated by MDS plot.
a
b
c
d
e
f
Figure 3. Some examples of abundance distribution for single species in the mesozooplankton of the Gulf of Vlore. a Diaixis sp. (Crustacea, Copepoda, Calanoida), during Spring, linked to the less confined situations; b Lucicutia flavicornis, during Spring, more abundant in the Gulf; c Oithona nana (Crustecea, Copepoda, Cyclopoida), during Spring, widespread in the study area; d Holothuroidea auricularia, during Winter, exclusive of the only Gulf waters; e Penilia avirostris (Crustacea, Cladocera), during Spring, linked to the Gulf; f Obelia sp. (Cnidaria, Hydrozoa), during Winter, linked to the Gulf coastal waters.
The SIMPER procedure associated with MDS plot of all samples identified the species responsible for the biotic characterization of each sampling season . The categories responsible for the average dissimilarity among mesozooplankton assemblages of spring 2007 were Acartia clausi, Acartiidae, and Centropagidae copepodids (all belonging to Crustacea Copepoda), together with the cladocerans Penilia avirostris and Evadne spinifera. The average dissimilarity among assemblages during winter 2008 was represented by Holothuroidea auricularia, the appendicularia Fritillaria pellucida, the copepod Ctenocalanus sp., undetermined stages of Calanoida, and Oncaea minuta.
Discussion The present report of 198 categories, if merged with the preceding one (Moscatello et al., 2011) on phyto and micro-zooplankton, concludes an important contribution to the knowledge of the Marine plankton diversity for the Albanian coast. The comparison with preceding studies also conducted elsewhere on the zooplankton of the same Mediterranean area (South Adriatic â&#x20AC;&#x201C; North Ionian seas) suggests that the species richness is noteworthy and well in accordance with
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International Conference MarCoastEcos2012, Tirana, Albania, 25-28 April 2012
the affirmation of Hajderi et al., (1998) who showed a species richness increase from North (the Adriatic Sea) towards South (the Ionian Sea).
2004), along the South Dalmatian coast of the Adriatic Sea. The higher numbers recorded from the Taranto Seas (North Ionian tip) from Vaglio (unpublished data) is in accordance with a more intense sampling effort (504 samples over 2 years) in that study. If compared with the study of the same Gulf bottoms (Maiorano et al., 2011), the Vlora plankton compartment appears interestingly rich of species, although the monotonous composition of the bottom (mud) and the fact that the study of the benthos relied on only one season could explain its relative species poorness. More in detail it appears interesting a comparison among the meroplankton here reported and information available for the benthos composition. The large dominance of auricularia larvae (Holothuroidea) is easily connectable with the dominant Labidoplax population of all the bottom muds of the Gulf. On the other side, the richness of meroplanktonic Hydrozoa (17 taxa) into the plankton, has not a comparable alternative in the benthos (2 taxa) thus allowing to admit a role of the narrow coastal rocky zone in the propagule (medusae) injection into the plankton. The comparison among meroplanktonic Polychaeta (16 taxa, mostly families) with benthic ones (53 taxa, belonging to 24 different families) has to be carried out carefully due to the different level of identification. This notwithstanding, at least in 6 cases (Magelona sp., Alciopidae, Chrysopetalidae, Goniadidae, Hesionidae, and Oweniidae larvae) here reported, it has not been found any correspondence with the benthic fauna of Maiorano et al (2011), probably due to the presence of rocky bottom species which were not considered by the reported study.
Group average Transform: Fourth root Resemblance: S17 Bray Curtis similarity
50
Similarity
60 70 80
C4 7
B1 7
C2 7
D2 7
B2 7
C3 7
G2 7
D1 7
G3 7
D4 7
D3 7
B4 7
G4 7
A3 7
A1 7
A2 7
A2 8
A1 8
D4 8
B1 8
D2 8
D3 8
B2 8
C3 8
D1 8
C2 8
B4 8
G2 8
A3 8
C4 8
G4 8
100
G3 8
90
Samples Transform: Fourth root Resemblance: S17 Bray Curtis similarity 2D Stress: 0,14
Space A B C D G
Table 3. Global test for differences between space groups (across all time groups). Sample statistic (Global R): 0,328; Significance level of sample statistic: 0,1% Number of permutations: 999 (Random sample from a large number); Number of permuted statistics greater than or equal to Global R: 0. In red, the significant differences (p<0,01).
Pairwise Tests Groups A, B A, C A, D A, G B, C B, D B, G C, D C, G D, G
Transform: Fourth root Resemblance: S17 Bray Curtis similarity 2D Stress: 0,14
Time 1 2
R Statistic 0,093 0,278 0,5 0,574 0,037 0,213 0,648 -0,056 0,63 0,417
Significance Level % 34 4 0,1 1 46 4 1 66,4 1 2,2
Possible Permutations 100 100 1225 100 100 1225 100 1225 100 1225
Actual Permutations 100 100 999 100 100 999 100 999 100 999
Number Observed 34 4 0 1 46 39 1 663 1 21
This result encourages to refine the knowledge (with a more prolonged and timely frequent sampling) also to sustain the necessity to manage the marine environment of the Gulf of Vlore, where tourism, fishery and protection policies are asking data to work on.
Figure 4. Nonparametric multidimensional scaling representation of mesozooplankton samples collected in Spring (May-June) 2007 (I CISM cruise â&#x20AC;&#x201C; Time 1) and Winter (January) 2008 (II CISM cruise â&#x20AC;&#x201C; Time 2), with superimposed cluster at similarity level of 40%. A, B, C, D, G represent transects comprising 18 sampling stations, from inner bay to open sea.
In fact, even if we consider only copepods (however they are the most important component of the zooplankton) the number of species in the present study is higher than that reported from the bays of Dubrovnik (Gamulin, 1979), Kastela (Regner, 1985), and Maliston (Lucic & Onofri, Proceedings
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The statistical comparison of the stations allows us to distinctly separate the Mezocanal area (stations G) from all the Gulf (stations A, B, C, D). The presence of some ecological indicators (e.g. Acartia clausi, Oithona nana, Oikopleura sp.) testifies for a not high level of confinement of the Gulf. Some copepods (e.g., Acartia margalefi, Paracartia latisetosa) typical of confined, more internal, brackish waters (see Belmonte et al., 2009), were reported only episodically and never in high numbers in the Gulf of Vlore. We have to consider that samplings were conducted with a research vessel (the oceanographic ship Universitatis) hence they were obliged to come from sites with an important depth (10 m at least). The confinement, on the contrary, is enhanced by shallowness of waters, and their relative isolation from the neighboring sea (as in lagoons and coastal lakes). As a consequence, the present study did not care with such a kind of environmental situation. To tell the truth, such shallow confined waters are not available and/or well identifiable in the Gulf of Vlore, where the depth of -10 m is very close to the coast in each point. The Gulf di per se could be an isolated area from the neighboring sea, but its large water volume (maximum depth, -54 m) probably is enough to avoid the stressing
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Oral presentations: Biodiversity and ecosystem functioning
International Conference MarCoastEcos2012, Tirana, Albania, 25-28 April 2012
variations of conditions (salinity and temperature, overall), which typically occur in confined waters. A certain difference is evident between the two opposite coasts of the Gulf. In the clusterization is easy to note as A3 B4 C4 (the East coast of the Gulf) group together, and well distinct from the group C2, D1, G2 (the West coast of the Gulf). This situation is easily referable to the anthropization of the East coast of the Gulf where the beach tourism asked the building of 50 hotels along 14 km of coastline, with severe consequences on the growth of sedimentation rate along the submerged coast (Fraschetti et al., 2011). The Karaburun coast, on the contrary, has been affected only by 2 military settlements until 1989, and nothing else from that date, when they were completely abandoned.
Giangrande, A., Geraci, S., Belmonte, G. (1994). Life cycle and life history diversity in marine invertebrates, and implications in community dynamics. Oceanography and Marine Biology Annu. Rev. (32): 305-333.
Guelorget, O., Perthuisot, J.P. (1992). Paralic Ecosystem. Biological organization and functioning. Vie et Milieu. 42 (2): 215-251. Hajdëri, E. (1998). Copepodi di acque epipelagiche nell’Adriatico meridionale (struttura, distribuzione e dinamica stagionale). Ecumenica Editrice publisher, Bari.: 58-132. Hajdëri, E., Casavola, N., Marano, G. (1993). Osservazioni sulla distribuzione dei Cladoceri nell’Adriatico Pugliese. Biologia Marina Mediterranea. (1).: 59-62.
Acknowledgments The present study has been funded by INTERREG III Italy-Albania Programme in the framework of CISM Project (Technical Assistance for Establishing and Management of an International Center for Marine Studies in Albania). The authors thank the crew of R/V Universitatis (CoNISMa) for the valuable field assistance.
Hajdëri, E., Casavola, N., Marano, G. (1994). Indagini preliminari sui Copepodi nel Canale d’Otranto. Biologia Marina Mediterranea. (1): 113-118. Hajdëri, E., Marano, G. (1998). Mediterranea. (5): 748-749.
Copepodi planctonici delle acque costiere di Bari. Biologia Marina
Hajdëri, E., Casavola, N. (2001). Copepods and zooplankton biomass from the open waters of the South Adriatic Sea. Albanian Journal of Natural and Technological Sciences. (11): 52-53.
References Amanieu, M., Lasserre, G. (1982). Organisation et évolution des peuplements lagunaires. Oceanologica Acta, SP.: 201-213. Badosa, A., Boix, D., Brucet, S., López-Flores, R., Gascón, S., Quintana, X.D. (2007). Zooplankton taxonomic and size diversity in Mediterranean coastal lagoons (NE Iberian Peninsula): Influence of hydrology, nutrient composition, food resource availability and predation. Estuarine, Coastal Shelf Sciences 71: 335-346. Belmonte, G., Moscatello, S., Pati, A.C., Posi, M. (2009). Lo zooplancton. In: Belmonte G. (ed.) Biodiversità ed Ecologia del Lago di Acquatina. Thalassia Salentina 31 Suppl.: 37-48. Belmonte, G., Cavallo, A. (1997). Body size and its variability in the copepod Acartia margalefi (Calanoida) from Lake Acquatina (SE Italy). Italian Journal of Zoology. (64): 377-382. Belmonte, G., Fanelli, G., Gravili, C., Rubino, F. (2001). Composition, Distribution and Seasonality of zooplankton in Taranto Seas (Ionian Sea, Italy). Biologia Marina Mediterranea. (8): 352-362. Blackburn, T.M., Gaston, K.J. (1994). Animal body size distributions: patterns, mechanisms and implications. Trends in Ecology and Evolution. (19): 471-474. Calbet, A., Garrido, S., Saiz, E., Alcaraz, M., Duarte, C.M. (2001). Annual zooplankton succession in coastal NW Mediterranean waters: the importance of smaller size fractions. Journal of Plankton Research. (23): 319-331. Clarke, K.R. (1993). Non-parametric multivariate analysis of changes in community structure. Australian Journal of Ecology. (18):117-143. Clarke, K.R., Warwick, R.M. (1994). 144.
Grandori, R. (1913). I copepodi pelagici raccolti nell’Adriatico nelle crociere III-VII del R. Comitato Talassografico Italiano. R. Comitato Talassografico Italiano, Memoria XXVIII. (62): 3.
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Denitto, F., Miglietta, M.P., Boero, F. (2007). Life cycle of Bougainvillia nana Hartlaub, 1911 (Cnidaria, Hydrozoa, Bougainvillidae) from Italy, with a discussion on the presence of the cosmopolitan Bougainvillia muscus in the Mediterranean Sea. Journal of Marine Biological Association UK. (87): 853-857. Elliott, M., Quintino, V. (2007). The estuarine quality paradox, environmental homeostasis and the difficulty of detecting anthropogenic stress in naturally stressed areas. Marine Pollution Bulletin. (54): 640-645. Fraschetti, S., Terlizzi, A., Guarnieri, G., Pizzolante, F., D’Ambrosio, P., Maiorano, P., Beqiraj, S., Boero, F. (2011). Effects of Unplanned Development on Marine Biodiversity: A Lesson from Albania (Central Mediterranean Sea). Journal of Coastal Research. (58): 96-115. Gamulin, T. (1979). Le zooplankton de la cote orientale de l’Adriatique. Acta Biologica. VIII (1-10): 176270.
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Hure, J., Scotto di Carlo, B. (1968). Comparazione tra lo zooplancton del Golfo di Napoli e dell’Adriatico meridionale presso Dubrovnik. Pubbl. Staz. Zool. Napoli. (36): 21-102. Lam Hoai, T., Rougier, C. (2001). Zooplankton assemblages and biomass during a 4-period survey in a northern Mediterranean coastal lagoon. Water Research. (1): 271-283. Lucic, D., Onofri, V. (1990). Seasonal variation of neritic mesozooplankton in Mali ston bay (Southern Adriatic). Acta Adriatica. 31 (1/2): 117-137. Mangoni, O., Margiotta, F., Saggiomo, M., Santarpia, I., Budillon, G., Saggiomo, V. (2011). Trophic characterization of the pelagic Ecosystem in Vlora Bay (Albania). Journal of Coastal Research. (58): 69-76. Maiorano, P., Mastrototaro, F., Beqiraj, S., Costantino, G., Kashta, L., Gherardi, M., Sion, L., D’Ambrosio, P., Carlucci, R., D’Onghia, G., Tursi, A. (2011). Biological study of the benthic communities on the soft bottom of the Vlora Gulf (Albania). Journal of Coastal Research. (58): 95-105. Marano, G., Casavola, N., Hajdëri, E., Martino, G. (1989). Composizione e distribuzione della biomassa zooplanctonica nell’Adriatico meridionale. Nova Thalassia. 10 (Suppl. 1): 195-202. Moscatello, S., Belmonte, G. (2004). Active and resting stages of Zooplankton and its seasonal evolution in a hypersaline temporary pond of the Mediterranean coast (the “Vecchia Salina”, Torre Colimena, SE Italy). Scientia Marina. 68 (Suppl. 1): 491-500. Moscatello, S., Belmonte, G. (2006). A preliminary plan for the study of zooplankton in the Gulf of Vlorë (Albania). Thalassia Salentina. (29): 61-68. Moscatello, S., Caroppo, C., Hajdëri, E., Belmonte, G. (2011). Space distribution of phyto- and microzooplankton in the Vlora Bay (Southern Albania, Mediterranean Sea). Journal of Coastal Research, Special Issue. (58): 80-94. Razouls, C. (1995). Répartition géographique chez les copépodes calanoïdes. Neocopepoda Gymnoplea Calanoida. Ann. Institut. Océanogr. (71): 81–404. Regner, S. (1985). Seasonal and Multiannual dynamics of copepods in the middle Adriatic. Acta Adriatica. 26 (2): 11-99. Robinson, A.R., Leslie, W.G., Theocharis, A., Lascaratos, A. (2001). Mediterranean Sea circulation. In: Encyclopedia of Oceanic Sciences, Academic Press.: 1689–1706 Rubino, F., Saracino, D.O., Fanelli, G., Belmonte, G., Miglietta, A.M., Boero, F. (1998). Life cycles and pelago-benthos interactions. Biologia Marina Mediterranea. (5): 253-259. Uye, S. I. (1994). Replacement of large copepods by small ones with eutrophication of embayments: cause and consequence. Hydrobiologia. (292/93): 513-519.
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International Conference MarCoastEcos2012, Tirana, Albania, 25-28 April 2012
SEVEN YEARS OF SURVEY (2004 - 2010) ON REPRODUCTION OF SEA TURTLES ON SHKAÏFATE BEACH, SYRIAN COAST (PROPOSED AS PROTECTED AREA) *1, 2,
Adib Saad, 3Alain Rees, 2Ahmad Soulaiman
1
Tishreen University, P.O.Box 1408 Lattakia, Syria; Syrian Society for Aquatic Environment Protection (SSAEP) 3 Greek Society for Sea Turtles Protection (ARCHELON) * E-mail: adibsaad@scs-net.org
2
Abstract In this work we present results of nesting turtles survey during seven years: 2004 – 2010, which were conducted around the coast. We found that there is sparse nesting along the coast between Shkaifat and Snawbar (south of Lattakia city). Along a 12.5 km stretch of coast. Results from the 2004- 2010 nesting season confirmed that a Shkaifat- Snawbar beach near Latakia in Syria was an important nesting site for green turtles in the Mediterranean. Keywords: sea turtles nesting, conservation, Levantine Basin, Syria
Introduction The presence of loggerhead (Caretta caretta) and green sea turtles (Chelonia mydas) off the coast of Syria, was first reported by Gruvel [1], but nesting on the country’s beaches was not indicated. The next turtle information to come out of Syria resulted from a rapid assessment survey in 1991 that identified low-level nesting concentrated on a beach south of Lattakia City[2]. Local researchers noted incidental turtle captures in beach seines, and also observed turtles stranded along the coast [3]. Since 2004 a more extensive coastal survey was undertaken, primarily to better identify Syria’s actual and potential nesting populations [4]. Both nocturnal surveys during the nesting season and co-operative efforts with fishermen afforded the first opportunities to observe turtles in the wild, to obtain basic biometric data and tag the turtles before they returned to the sea after nesting or were released after being caught in fishing nets.
Material and methods From last week of May to second week of October the 7.5 km Shkaïfat beach between North Jableh and Snowbar, 35°28'00"N, 35°51'45"E was surveyed in the early morning for evidence of sea turtle nesting, nest hatching and events that may have affected the incubation of nests, such as inundation by storm waves or depredation. The adjoining beach to the north, from Snowbar to the river Al Kabir Al- Shamali next to Lattakia, 5 km to the north, was surveyed, as a continuation of the daily survey, 10 times at weekly intervals to record the same information. Emergence tracks from adult turtles were checked for species and evidence of nesting and the track recorded as either a nesting or non-nesting emergence. Nesting species was determined by appearance of the track [5] and by maximum width of the track. In the eastern Mediterranean, loggerhead turtles are generally far smaller than green turtles, and hence their track widths are generally much narrower. Additionally nest excavation often afforded confirmation of species by identification of dead or live hatchlings or embryos. To determine the movement of sea turtles during and after the reproduction period, we tagged 78 individual during 2004- 2010 with metal tags contain the name and address of the team leader. Tags used in this investigation were model 681, ‘monel’ metal tags produced by the National Band & Tag Company (Kentucky, USA), placed in the trailing edge of the fore flippers (Figure 2). Turtles were double tagged whenever possible to avoid loss of turtle identity, which would happen if a turtle were to lose its single tag.
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Figure 1. Location of Shkaïfat beach, south of Lattakia (proposed as coastal protected area) in the Syrian coast
Figure 2. Adib Saad and membes of ssaep tagging a green turtle
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Results and discussion During 2004, 2006, 2008 , 2009 and 2010 we noticed 8, 15 ,21,19 and 18.7 nests per Km ( respectively) for the green turtle Chelonia mydas, as for Caretta caretta, we recorded many nests and spawning sites in the same beach, but in less number (Table 1 & Figure 3). During 2005 and 2007, the number of green turtle nests was much lower ( 3 and 2 nest per km of beach). Overall, these results indicate that this surveyed area is among the best sixth coastal zones suitable for the reproduction of the green sea turtles along the Mediterranean coast. Syria may also play a significant role hosting foraging turtles, as loggerheads from Cyprus, Turkey and Greece and have been shown to forage in near shore Syrian waters [6]. Since green turtle nesting was discovered in 2004, repeated surveys have indicated that Lattakia beach hosts a regionally important rookery. This, together with the presence of lower frequency nesting at a few other beaches places Syria as the third most important country, after Turkey and Cyprus, for green turtle nesting in the Mediterranean.
Saad, A., Rees, A., (2004). Status of Marine turtles in Syria 2004: Focus on nesting beach investigation (Case study and recommendation for future research). Proceeding of the workshop INOC Meknas. Marroco, 2-5 November 2004. Rees, A.F., Saad, A., Jony, M. (2008). Discovery of a regionally important green turtle Chelonia mydas rookery in Syria. Oryx. 42. (3): 456-459. Schroeder, B., Murphy, S. (1999). Population surveys (ground and aerial) on nesting beaches. In Research and Management Techniques for the Conservation of Sea Turtles (eds K.L. Eckert, K.A. Bjorndal, F.A. Abreu-Grobois & M. Donnelly). 45–556. Rees, A.F., Saad, A., Jony, M. (2010). Syria. 233-243 in: Casale, P. and Margaritoulis, D. (Eds.) Sea turtles in the Mediterranean: Distribution, threats and conservation priorities. 2010. Gland, Switzerland: IUCN. 294 pp.)
Table 1. Annual variation of nest number of green turtles and loggerhead on the Shkaifat beach (south of Lattakia) during seven years of survey. Year 2004 2005 2006 2007 2008 2009 2010
Number of nest Green turtle Loggerhead turtle 104 5 198 29 273 218 234
6 1 8 5 16 22 26
Number of surveys 50 60 70 60 70 60 42
Figure 3. Variation in number of turtle nests (C. caretta & C. mydas) on Shkaifat beach (South of Lattakia ) during seven years of survey
References Gruvel, A. (1931). Les Etats de Syrie. Richesses marines et fluviales.Exploitation actuelle-Avenir. Biblioteque de la faune des colonies Francaises III.Paris, société d'Editions Geographiques, Maritimes et Coloniales. Kasparek, M. (1995). The Nesting of Marine Turtles on the coast of Syria. Zoology in the Middle East. (11): 51-62. Proceedings
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Oral presentations: Biodiversity and ecosystem functioning
International Conference MarCoastEcos2012, Tirana, Albania, 25-28 April 2012
DATA ABOUT LOGGERHEAD SEA TURTLE (CARETTA CARETTA L., 1758) IN PATOKU LAGOON, ALBANIA
protection and management of marine and coastal biodiversity in such areas would be of crucial importance. Improve the capacity to study and conserve biodiversity at the abovementioned sites, would help to ensure environmental sustainability.
1*
Enerit Saçdanaku, 2Idriz Haxhiu
Material and methods
1
Departament of Biology, Faculty of Technical Sciences, University of Vlora ‘Ismail Qemali’, Albania 2 University Vitrina, Tirana, Albania * E-mail: eneriti@gmail.com
1. Study area
Abstract Data about loggerhead sea turtle (Caretta caretta L.,1758) conducted in Patoku area (Drini Bay, Western Albania) during 2008, within the project focused on the monitoring and conservation of important sea turtle feeding grounds in the Patoku area (2008-10), supported by MEDASSET. About 105 individuals were captured in total as bycatch in stavnike fish-traps and trawling operations in this area; all them were tagged, using Stockbrands titanium tags. Moreover, the relative data about morphometry and bioecology was assessed. About 95 individuals were tagged for the first time; 10 individuals were remigrants (tagged before 2008); while 16 individuals were recaptured within the same year. The largest number were captured in June (63 individuals) and only one in August and December, respectively. Based on morphometric size-classes, the largest number belonged to 60 cm class (46 individuals), while 2 individuals belonged to the 80 cm class. One of the most important morphometric aspects was the tail measurements: it is a simple technique, yet very important to show sexual differentiation in sea turtles. Hence, almost the whole population captured (102 individuals) consisted of 19.6% male, 39.2% female and 41.2% undetermined. Most of individuals presented epibiontic flora (mainly green algae) and epibiontic invertebrates, Balanus spp. were common; Lepas spp. were occasional, gastropods and bivalves were relatively rare. It was concluded that Drini Bay is a regionally and nationally important habitat that is used by sea turtles for foraging, as a refuge and as part of a key migratory corridor between the Ionian and Adriatic Seas.
In the northernmost part of the Western Lowlands of Albania there is a lagoon at Patoku region [N41o38.191’; E019o35.327’]. This lagoon is part of Drini Bay, which is a shallow sea (maximum depth 47 m) with a sand and mud substratum dominated by bivalves and crabs. Five sedimentladen rivers enter the bay: Buna, Drini, Mati, Droja and Ishmi.
Keywords: Caretta caretta, morphometry, tagging, epibiontic, Patoku region.
Introduction Figure 1. Drini Bay (adapted by M. White)
There are four species of sea turtles documented from Albanian offshore waters: Loggerhead turtle, Caretta caretta, is the most common (Zeko & Puzanov, 1960; Haxhiu, 1981, 1985, 1995, 1997, 1998, 2005, 2010) The green turtle, Chelonia mydas, is rare (Zeko & Puzanov, 1960; Haxhiu, 1981, 1985, 1997, 1998) Leatherback turtle, Dermochelis coriacea, very rare. The hawksbill turtle, Eritmochelys imbricata, a special occasion in Albanian waters (Frommhold, 1959; Haxhiu, 2010).
2. Stavnikes One of the method used in this study was to monitor turtles that were caught incidentally by fisheries (i.e. ‘bycatch’); and in particular from a method of fishing that uses traps, which are known as ‘stavnikes’. Stavnikes are a type of fish‐trap, originating in Russia that arrived in Albania around 30 years ago, and were forgotten until about 2003; when the Patoku fishermen started to use them again (Haxhiu, 2010).
The first three species of marine turtle are exhibited in the Museum of Natural Science in Tirana. Studies and publications on sea turtles in Albania are scarce (Zeko & Puzanov, 1960; Haxhiu, 1981, 1985, 1995, 1997, 1998; Haxhiu & Oruci, 1998; Haxhiu & Rumano, 2005; Haxhiu, 2010). They concern sporadic observations and descriptive geographic distributions of turtles in Albania. Focused studies have been carried out between 2002 – 2009. During this period, 1027 individual of Caretta caretta were studied (75 of wich were found dead) and 18 individual of Chelonia mydas (Haxhiu, 2005, 2010). Loggerheads are considered endangered species and are protected by the International Union for the Conservation of Nature. Untended fishing gear is responsible for many loggerhead deaths. Turtles may also suffocate if they are trapped in fishing trawls. Turtle excluder devices (TEDs) have been implemented in efforts to reduce mortality by providing an escape route for the turtles. Loss of suitable nesting beaches and the introduction of exotic predators have also taken a toll on loggerhead populations. Efforts to restore their numbers will require international cooperation since the turtles roam vast marine areas and critical nesting beaches are scattered across several countries. Their relatively high presence in Patoku region means that this area shows significant ecological importance, rich in habitats that can help in the conservation of endangered migratory species (like marine turtles, etc.). Building knowledge and improving the Proceedings
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Figure 2. Typical design of a stavnike fish‐trap (after I. Haxhiu)
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International Conference MarCoastEcos2012, Tirana, Albania, 25-28 April 2012
A long barrier net extends from the fish‐traps to the beach (Ishmi stavnike was 1800 m offshore, coordinates: [N41o36.198’; E019o33.349’]; Mati only 200 m, coordinates: [N41o38.512’; E019o34.126’]); the traps are constructed to allow entry from either side of the barrier net. When fish or turtles encounter the barrier they have three choices: to turn left, right, or to go back the way they came; an area they may have just foraged. Turning beachwards leads them into shallower water, but any animals entering the traps’ reception area are guided into successive chambers; escape from these is difficult although not impossible.
Results and discussion 1.
Distribution of individual (Caretta caretta) by month
In the following chart is shown the distribution of individual of C. caretta by month:
3. Morphometric data The curve carapace length (CCL) and curved carapace width (CCW) were measured and turtles allocated into 10 cm size – classes (length - frequency distribution) based on their CCL e.g. 40 cm size – class range: 40.0 – 49.9 cm et seq. (White, 2007). As an indicator of the stage of sexual development, three measurements were recorded from the tail: a) Distance from posterior margin of plastron to midline of cloacal opening (Plas – clo) b) Total tail length (TTL) c) Distance from tip of tail to posterior margin of the carapace (+/- cara) As a very important elements in identifying the individual of turltes we have also counted the epidermal scales of the carapace (nuchal, coastal and marginal scales) as well as head scales (prefrontal and frontoparietal).
4. Tagging The first turtle tagging project in Albania began at the end of 2002, using Dalton’s plastic Rototags (provided by RAC/SPA, Tunis). Suggett & Houghton (1998) provided evidence that Rototags can increase the risk of turtles becoming entangled in fishing gear, and so in this study we used a single Stockbrand’s titanium tag (these tags lock into a closed u‐shape).
Figure 4. Distribution of individual (Caretta caretta) by months
As it is shown from the chart the largest number of individual has resulted in June and July. It is seen that we have a disproposal in distribution between June and July and the other months. This is because of stavnikes, wich have been working till the mid of August. Based on the previous studies related to the distribution of C. caretta in this area (Haxhiu, 2005, 2007) we have this view: in 2002 the largest number of individual resulted in September (50 individual); in 2003 in May (71 individual); 2004 in July (24 individual); in 2005 in June (25 individual); 2006 in June (15 individual). 2. Size – classes In the following table and chart is given the distribution of turtles by month, allocated into 10 cm size – classes (length - frequency distribution) based on their CCL e.g. 40 cm size – class range: 40.0 – 49.9 cm et seq. (White, 2007). Table 1. Number of loggerhead in each cm size – class of CCL. CCL June July August September December Total
40
50
60
70
80
Total
0 2 1 1 0 4
17 10 0 0 0 27
26 20 0 0 0 46
17 4 0 1 1 23
2 0 0 0 0 2
62 36 1 2 1 102
Figure 3. Stockbrand’s titanium tag, put on the flipper of the turtle (Photo M. White)
The first titanium tag was applied in July 2008; these tags were marked with an Albanian address, in order to reinforce the conservation message; fishermen thought that the Rototags had been applied in Tunisia due to the RAC/SPA address marked on the tag. When Roto‐tagged turtles were recaptured, the plastic tags were removed and replaced with a titanium tag.
Figure 5. General distribution of individual of C. caretta by size – class for 5 months (June, July, August, September, December) Proceedings
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From the above table and chart it is clearly seen that the largest number of individual of C. caretta belongs to 60 cm size – class (46 individuals), while the smallest number to the 80 cm size – class (2 individual). 3. Head epidermal scales As a very important elements in identifying the individual of turltes we have also counted the epidermal scales of head (prefrontals and frontoparietals). The following charts shows the distribution of individual related to the number of prefrontal and frontoparietal scales:
Figure 8. Distribution of individual by the number of frontoparietals scales
In frontoparietals scales we have included all those scales that touch the parietal (see Figure 6). There is a certain number of these scales in Caretta caretta. From the Figure 8, it is seen that this number varies from 9 – 15 frontoparietals and the mode is 12 with 35 individuals.
4.
Determination of sex
The sex of marine turtles can be determined easily in mature individuals (adults). This is because of some secondary characteristics features, as can be: males tail length; size and morphology of carapace; the hole in the plastron or the development of nail in the front limbs of a male individual. The most obvious feature to an adult male is the tail, which is too long and extend outside the carapace (see Figure 10).
Figure 6. Demonstration of head scales (Photo: I. Haxhiu)
Figure 10. The extended tail of an adult male loggerhead (left) A male individual of C. caretta (right) Figure 7. Distribution of individual by the number of prefrontal scales
Regarding to the prefrontal scales in C. caretta their numbers is always 4 or more, but never less than 4. While to the other species Chelonia mydas this number is always 2. In this way the number of prefrontal scales it is used as a taxonomic element for the identification of species. Form the chart (Figure 7), it is seen that the largest number of individual have had 4 and 5 prefrontal scales (which is normal), while the smallest number of individual have had 8 prefrontal scales (this is very rare). While for the identification of individuals within the species we have been focused on the shape, size and number of frontoparietals scales (photo – recognition, White, 2006).
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While when we talk abuot an individual adult female, it can be easily traced because they have a short tail and in most cases the length of the tail does not extend out of carapace (see Figure 11).
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5. Epibionts Epiobionts (epibiontic flora and epibiontic fauna) is very widespread in sea turltles (Oliverio et al., 1992). The individual of C.caretta were studied for the presence of epibionts. Most of individuals presented epibiontic flora (mainly green algae) and epibiontic invertebrates, Balanus spp. were common; Lepas spp. were occasional, gastropods and bivalves were relatively rare. For all the individual studied has resulted that they were overloaded with epiobionts (epibiontic fauna and epibiontic flora) in a percentage of 48.6 % against them who were clean (without epibionts) in a percentage of 51.4 % (see Figure 13).
Figure 11. A female individual of C. caretta (left). Demonstration of morphological elements or sex determination to an adult male (right)
The difficulty in determining the sex of individuals stands to those who are sexually unmatured (Juveniles). This is because the length of the tail to the juvenile is not enough developed and it can not be used as an element to determine their sex (Limpus, 1985; Wibbles, 1988). In determining their sex are used other methods that are not based on morphological elements. One of the methods can be direct observation of the gonads, through examination with special equipment (Wood et al., 1983; Limpus & Reed; Limpus, 1985). In this study we have classified the individual of C. caretta into three groups regarding to their sex: Female, male and undetermined (juvenile). For this we are based mainly on these morphological elements: Distance from posterior margin of plastron to midline of cloacal opening (Plas – clo); Total tail length (TTL); Distance from tip of tail to posterior margin of the carapace (+/- cara) (see Figure 11). Based on this classification has resulted that 41.17 % were female, 19.60 % male and 39. 21 % undetermined (juvenile). In the following chart is given this distribution of individual by sex. As it is seen in the following chart we have a dominance of female individual over the males and quite a large number of undetermined individual (juvenile).
Figure 12. Distribution of individual of C. caretta by sex given in percentage
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Figure 13. An individual of C. caretta overloaded with epibionts (Photo: I. Haxhiu)
Conclusions About 105 individuals were captured in total as bycatch in stavnike fish-traps and trawling operations in this area; all them were tagged, using Stockbrands titanium tags. About 95 individuals were tagged for the first time; 10 individuals were remigrants (tagged before 2008). Remigrants referres to previously‐tagged turtles captured inter‐annually. This is a very important data because it shows that Albania is part of their migratory routes. Turtles that were caught more than once in the same field‐season were referred to as ‘recaptures’. In our stduy resulted that 16 individuals were recaptured within the same year (2008). This data shows that this area could be a foraging habitat for those animal. From this study resulted that 41.17 % were female, 19.60 % male and 39. 21 % undetermined (juvenile). As it is seen we have quite a large number of female individual. This data can be considered as very important, because so far in Albanian coastline has not been found any nesting activity. Having these high percentage of female we can say that in the future Albanian coastline can be a potential nesting habitat for Caretta caretta. The distribution and lifestyle of male turtle is not as well known as that of females, because as it is known males spend all their life-cycle on the sea and is very difficult to study them. As the distribution and marine ecology of male turtles is poorly understood, this unusual assemblage can be considered an important and highly-significant finding. We can say that Patoku lagoon may be a male foraging and developmental habitat, as 19.60 % of all individual studied were males. In this study almost half (48.6%) of infividual of C. caretta were overloaded with epibionts (epibiontic fauna and flora). The most important is the fact that these epibionts does not cause any damages to turtles, except of making their body a little havy for swimming. Thus, their are not parazite to sea turtles, but they use the shell of these animals to fix on it and while turtles are swiming in differents habitats they feeds. From the three year project was concluded that Drini Bay is a regionally and nationally important habitat that is used by sea turtles for foraging, as a refuge and as part of a key migratory corridor between the Ionian and Adriatic Seas. 72
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References Haxhiu, I. (1979). Percaktues i Reptileve te Shqiperise. Shtepia Botuese e Librit Universitar. Tirane. 1 – 144. Haxhiu, I. (1980). Rezultate te studimit te reptileve ne vendin tone. Disertacion.‐ Biblioteke Kombetare, Tirane. 1‐102. Haxhiu, I. (1981). Emertime popullare te zvarranikeve ‐ Studime Filologjike. (4): 209‐ 217.
Haxhiu, I. (1985). Rezultate te studimit te breshkave ne vendin tone (Rendi Testudines) . Bul Shkenc. Nat. (2): 54‐60. Haxhiu, I. (1995). Results of studies on the Chelonians of Albania. Chelonian Conservation and Biology., Florida – USA. (1). Nr. 4 : 324‐327. Haxhiu, I. (1998). The Reptilia of Albania: species composition, distribution, habitats. Bonn Zool. Jb. Syst. (121): 321‐334. Haxhiu, I., Rumano, M. (2005). Conservation project of sea turtles in Patok, Albania. Second Mediterranean Conference on Marine Turtles. Kemer. 87-90.
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Haxhiu, I., (2010) Albania Pp. 5-28 in Casale, P. D. Magritoulis (Eds) 2010. Sea turtles in the Mediterranean: Distribution, threats conservation priorities. Gland, Swizerland: IUCN. 296. Haxhiu, I. (1998). The Reptiles of Albania: Species compositions, distribution, habitats. Bonn, zool. Beitz. (48): 35-37. Limpus, C. J. (1985). A study of loggerhead sea turtle, C. caretta in eastern Australia. Ph.D. disertation. Univ. Queensland, Brisbane, Australia. Oliverio, M., Gerosa, G., Cocco, M. (1992). First record of Pinctada radiata (Bivalvia, Pteriidae) epibiont on the loggerhead sea turtle Caretta caretta (Chelonia, Cheloniidae). Boll. Malacol.( 28): 149-152. Suggett DJ, Houghton JDR (1998) Possible link between sea turtle bycatch and flipper tagging in Greece. Marine Turtle Newsletter 81: 10‐11. White, M. G. (2007). Marine ecology of loggerhead sea turtles Caretta caretta (Linnaeus, 1758) in the Ionian Sea: Observation from Kefalonia and Lampedusa. Ph.D. Thesis, University College Cork, Irleand. 300. White, M. (2006). Photo‐recognition: a technique used to identify individual loggerhead turtles in the marine environment. In: Frick, M., A. Panagopoulou, A.F. Rees and K. Williams (Eds.), Book of Abstracts. Twenty‐Sixth Annual Symposium on Sea Turtle Biology and Conservation. International Sea Turtle Society. Crete, Greece. 376. White, M., Haxhiu, I., Kararaj, E., Mitro, M., Petri, L., Saçdanaku, E., Trezhnjevna, B., Boura, L., Grimanis, K., Robinson, P., Venizelos, L. (2010). Monitoring and Conservation of Important Sea Turtle Feeding Grounds in the Patok Area of Albania 2008‐2010. Project Report. Wood , J. R., Wood, F.E., Critchley, K.H., Wildt, D.E., Bush. M. (1983). Laparoscopy of the green sea turtle. British Journal of Herpetology. (6):323-327. Zeko, I., Puzanoi, V., (1960). Nje breshke oqeanike ne bregdetin tone [An oceanic turtle in our seaside]. Buletini I Shkencave Natyrore [Bulletin of Natural Sciences]. (4): 145-146.
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