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THE WASPS AND BEES (HYMENOPTERA: ACULEATA) OF RAMPART FIELD AND WEST STOW COUNTRY PARK IN SUFFOLK MICHAEL ARCHER The aim of this paper is to give a detailed investigation of the aculeate wasps and bees of Rampart Field, including those from West Stow Country Park which was mainly a study of the car park. Both sites are situated north-west of Bury St. Edmunds and just to the west of West Stow village. Rampart Field (TL7871) is a picnic place managed by Suffolk County Council. It has an area of 6·9 ha., is situated in the valley of the river Lark, and is a part of Breckland. The site consists of a valley slope with level ground at the valley bottom. Scots pine, gorse and bramble cover much of the slope, and heather with several species of herbs grows in the valley bottom. The shrubs and herbs provide food resources and nesting sites and the bare sandy patches associated with paths, banks and open areas are also important nesting sites. West Stow C.P. (TL8071), which has an area of 51 ha., is situated between King’s Forest and the River Lark. The site consists of Breck heath, woodland and a lake. Only the car park with its bare banks was surveyed to any great extent. These are important nesting sites for aculeate wasp and bee species. From Rampart Field 85 species of aculeate wasps and bees have been recorded, of which 17 species are of national importance. From an incomplete survey of West Stow Country Park 69 species of aculeate wasps and bees have been recorded, of which 12 species are of national importance. Methods Between 1983 and 2002, 13 visits were made to Rampart Field distributed throughout the year as follows: April (1 visit), May (2), June (2), July (3), August (4) and September (1). Between 1984 and 2002, 10 visits were made to West Stow C.P. as follows: May (2), June (3), July (2) and August (3). All the visits were made during warm sunny weather when the adult aculeate wasps and bees would be active. During each visit, approximately three hours for Rampart Field and two hours for West Stow C.P., all species of aculeate wasps and bees were recorded and usually collected with a hand net for later identification. In the following account the nomenclature can be related to Kloet & Hincks (1978). An up-to-date checklist can be found on the Bees, Wasps and Ants Recording Society (BWARS) web pages at www.bwars.com. Species Present and Seasonal Progression of Species A full list of the species recorded with authorities is given in the appendix. At the family and subfamily levels, Table 1 shows the taxonomic distribution of species and records. A record represents a specimen differing in one of the following three variables: name, sex and day of visit. The solitary wasp family, Sphecidae, and the solitary bee subfamilies, Andreninae and Halictinae, are the dominant groups in terms of number of species and records, although the Pompilidae are also well represented.
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Table 1. Number of species and records of aculeate wasps and bees recorded from Rampart Field (RF) and West Stow County Park (WS)
Solitary Wasps Chrysididae Tiphiidae Pompilidae Eumeninae Sphecidae Total Solitary Wasps Solitary Bees Colletinae Adreninae Halictinae Melittinae Megachilinae Anthophorinae Total Solitary Bees Total Solitary Wasps and Bees Vespinae Apinae Total Social Species Total Wasps & Bees
Species (RF)
Species (WF)
Total Species
Records (RF)
Records (WS)
4 1 6 2 24 37
6 1 5 1 17 30
7 1 9 3 30 50
8 4 19 2 65 98
10 1 17 1 44 73
4 8 15 2 5 5 39
6 9 11 0 2 1 29
7 13 18 2 6 5 51
9 16 29 4 5 7 70
11 13 19 0 6 4 53
76 2 7 9 85
59 2 8 10 69
101 3 9 12 113
168
126
July was the best month for recording and the first recording of solitary wasp species at both Rampart Field and West Stow C.P. (Table 2). In addition, at Rampart Field June and August were also good recording months and June was a good month for the first recording of species. At West Stow C.P. August was a good month for the recording of species. Most frequently encountered species at Rampart Field were: the spider hunter. Episyron rufipes, the caterpillar hunters Ammophila sabulosa and Podalonia affinis, the weevil hunter Cerceris arenaria, the heteropteran nymph hunter Astata boops with its parasite Hedychridium roseum, and the fly hunter Oxybelus uniglumis. The most frequently encountered species at West Stow C.P. were Episyron rufipes, Ammophila sabulosa, the aphid hunters Diodontus tristis and D. minutus, the grasshopper nymph hunter Tachysphex pompiliformis with its parasite Hedychridium ardens, and Cerceris arenaria. All these solitary wasp host species are subterranean nesters. The best months for recording solitary bee species were May, June, July and August and July for first recording at Rampart Field (Table 2). May was the best month for recording and first recording at West Stow C.P. The most frequently encountered species at Rampart Field were: Andrena fuscipes, Colletes succinctus and its cleptoparasite Epeolus cruciger, Lasioglossum brevicorne, L. leucozonium, L. villosulum and L. calceatum with its probable
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Table 2. The number of species and first record of species of solitary wasps and bees recorded per month at Rampart Field (RF) and West Stow Country Park (WS)
Solitary Wasps Number of Species Rampart Field West Stow C.P. First Records Rampart Field West Stow C.P. Solitary Bees Number of Species Rampart Field West Stow C.P. First Records Rampart Field West Stow C.P
April
May
June
July
0 -
August
September
2 4
11 9
24 20
18 16
9 -
0 -
2 4
11 7
18 15
5 4
1 -
4 -
10 17
12 8
15 6
12 8
5 -
4 -
9 17
9 5
12 4
4 3
1 -
cleptoparasite Sphecodes monilicornis. All these host species are subterranean nesters and A. fuscipes and C. succinctus are particularly dependent on heather as a pollen food source. The most frequently encountered species at West Stow C.P. were Colletes fodiens with its cleptoparasite Epeolus variegatus, Megachile dorsalis (=M. leachella), Lasioglossum calceatum with Sphecodes monilicornis and L. leucozonium. M. dorsalis is usually associated with coastal sand dune sites. All the host species again are subterranean nesters. Species Quality According to Shirt (1987) six Red Data Book species have been found at Rampart Field (Podalonia affinis, Cerceris quinquefasciata, Philanthus triangulum, Halictus confusus, Lasioglossum brevicorne, Sphecodes reticulatus) and four species at West Stow C.P. (Podalonia affinis, Philanthus triangulum, Andrena tibialis, Lasioglossum brevicorne). Falk (1991) introduced the Notable status for species, a status that is lower than the Red Data Book status, where he indicated that the Red Data Book status of Andrena tibialis and Sphecodes reticulatus should be reduced to Notable status. In addition, the following species at Rampart Field would be Notable according to Falk: Evagetes dubius, Oxybelus argentatus, Lasioglossum quadrinotatum, Andrena humilis, Megachile dorsalis and Dasypoda hirtipes and at West Stow C.P.: Chrysis illigeri, Podalonia hirsuta, Microdynerus exilis, Lasioglossum quadrinotatum, Megachile dorsalis. Recent work carried out by BWARS indicates that further changes are necessary. To take account of these changes, Archer (1999, 2002) developed a national quality scoring system of high and low quality species. High quality species have a scarce, rare or very rare status while low quality species have a universal, widespread or restricted status. These Archer statuses for each species are given in the
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appendix. The one major change in status is that Philanthus triangulum changes its very rare high quality status to a widespread low quality status. This change in status reflects its relatively recent increase in range. By giving each of the 76 species of solitary wasps and bees an Archer national status a national quality score of 300 can be calculated (Table 3) with a national species quality score of 3·9 (300 divided by the 76 solitary species). A similar exercise for West Stow C.P. (Table 4) gives a quality score of 181 and a species quality score of 3·1. Since the survey of West Stow C.P. was not completed these estimates are only provisional. How do these scores compare with similar scores for other inland sandy East Anglian sites? Although the number of solitary and high quality species and hence quality scores are likely to be influenced by the areas of sites, the species quality scores are relatively independent of site area (Archer, 1999), so can be used to compare sites. Archer (2004) lists species quality scores for the solitary species for the sites at Elveden Center Park, Suffolk (4·0), Santon Downham, Norfolk (3·9) and Roydon Common, Norfolk (3·9). Such values probably represent the highest scores for East Anglian sites. The species quality score for Rampart Field (3·9) is similar to these. None of the social species recorded are of national importance and they can all be considered low quality species. Table 3. The Archer National Quality Scores of the solitary wasps and bees recorded from Rampart Field Status Universal Widespread Restricted Scarce Rare Very rare Total
Status Score (A) 1 2 4 8 16 32
No. Species (B)
Quality Score (A × B)
32 24 3 12 3 2 76
32 48 12 96 48 64 300
Species Quality Score 300/76 = 3·9 Table 4. The Archer National Qualities Scores of the solitary wasps and bees recorded from West Stow C.P. Status Universal Widespread Restricted Scarce Rare Total
Status Score (A)
No. Species (B)
Quality Score (A × B)
1 2 4 8 16
29 16 2 10 2 59
29 32 8 80 32 181
Species Quality Score 181/59 = 3·1
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Table 5. Non-parametric estimates of species richness at Rampart Field No. species recorded No. species estimated 95% confidence limits % of estimated species found
Chao estimate
Jackknife estimate
76 110 84–137 69·1
76 110 90–130 69·1
Estimating the Potential Number of Solitary Wasp and Bee Species One of the problems in the study of any site is the difficulty of not knowing how many more species are present, but not yet recorded. Advances in nonparametric statistical procedures offer a way of addressing this problem. Chao (in Colwell & Coddington, 1994) and Jackknife (Heltshe & Forrester, 1983) procedures estimate the potential number of species (species-richness) likely to be found after a number of sampling visits have occurred. The presence/ absence estimate of Chao is based on the number of species that are recorded in just one (singletons) or two (doubletons) samples in the survey. The Jackknife procedure is based on the singleton species. Because some aculeate species are only active in the spring or summer it is advisable that samples be distributed throughout the months of adult activity. The software to carry out these statistical procedures was provided by Pisces Conservation Ltd. In practice the software take one, two, etc. samples at random, each time calculating a mean estimate of species richness. The procedure is repeated several times for each number of samples. With an increasing number of samples the estimates may approach a constant value indicating a stabilized prediction of species richness. The estimates at different samples are given in Figs 1 and 2 for Rampart Field. The estimates are tending to stabilize with similar predicted species richness so that confidence can be had in the estimates. Table 5 shows the two species-richness estimates after all samples have been considered, with 95% confidence limits (i.e. there is a 95% chance that the actual number of species falls within this range). The final species-richness estimates for Rampart Field are 110 solitary species, of which nearly 70% have actually been recorded. Species-Area Relationship Another problem in the study of any site is the difficulty of knowing when the species list is sufficiently complete to enable reasonable comparison with other sites. The list of solitary species from Rampart Field can be considered reasonably complete from the species-richness analysis. It is therefore possible to compare the species-area relationship for Rampart Field with other sandy sites from south-east England. Fig. 3 shows a species-area plot for solitary species from 24 inland sandy sites from south-east England (Archer & Edwards, 2002) and Rampart Field. The species-area dot for Rampart Field falls within the range of the other sites. Thus Rampart Field has the expected number of solitary species for its area. Since the sites of south-east England represent the best aculeate sites in the U.K. for species richness, Rampart Field can be regarded as among the best aculeate sites in the U.K.
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Figure 1. The Chao presence/absence estimate of species-richness of species of solitary wasps and bees from Rampart Field.
Figure. 2. The Jackknife estimate of species-richness of species of solitary wasps and bees from Rampart Field.
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Figure 3. A species-area plot based on the solitary wasp and bee species from 24 inland sandy sites in south-east England and Rampart Field. The correlation coefficient of the species-area plot of the 25 sites indicates a highly significant positive linear relationship (r = 0·91, p <0·001) with 83% of the variation of the number of species between sites explained by the variation in the area of the sites. The species-area equation is: ln number of species = 4·21 + 0·1648 x ln area (ha.). Two other statistics from the regression equation are: the mean number of species of solitary wasps and bees expected from the best sites on one hectare is 67 species (anti-log 4·21) and, in order to double the number of solitary species of wasps and bees the mean area would need to be increased about 67-fold (2 raised to the power of 1/0.1648). Using the regression equation the number of solitary species that might be expected from West Stow C.P. would be 128 species compared with the 59 species found. The lower number of species found indicates that West Stow C.P is a less favourable site for solitary species, or that further sampling is required. Since sampling of this site has not been completed further sampling is recommended. Cleptoparasitic Load The cleptoparastic load (CL) is the percentage of aculeate species that are cleptoparasites (or parasitoids) on other host aculeates. Wcislo (1987) showed that parasite behaviour among aculeate Hymenoptera correlated with geographical latitude. Thus the parasite rates are higher in temperate regions as host populations are more synchronized in their life-history characteristics. This finding probably does not hold for desert climates where the occurrence of rainfall would tend to synchronize life-history characteristics.
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From a review of the literature Wcislo (1987) found that the CLs for bees in Europe varied between 16% and 33%, a range of 17%. Therefore, CLs for sites in Britain should have similar values. For the north Midlands and north England, the CLs for species of solitary bees varies from 21·7%–36·6% (range 14·9%) (Archer, 1999). The CL for Rampart Field falls with this range while the CL for West Stow C.P. falls below this range (Table 6). The low CL for West Stow C.P. is a consequence of an incomplete survey and probably indicates that probably further cleptoparasitic solitary bee species will be found. Wcislo (1987) gives no CLs for wasps, but Archer (1999) found that CLs of solitary wasps for sites from north Midlands and north England varies from 10·3%–22·2%. The solitary wasp CLs for Rampart Field and West Stow C.P. (Table 6) fall within this range or very near to this range. All the social wasp species are host species, as are the bumble bee species, except for Bombus vestalis whose host is usually B. terrestris and B. campestris whose host is B. pascuorum. Table 6. The relative frequency of the cleptoparasitic (or parasitoid) species among the solitary wasp and bee species recorded from Rampart Field and West Stow Country Park No. hosts (H)
No. cleptoparasites (C)
Cleptoparasitic Load CL = 100× C/(H+C)
Solitary Wasps Rampart Field West Stow C.P.
30 22
6 7
16·7 24·1
Solitary Bees Rampart Field West Stow C.P.
28 26
11 3
28·2 10·3
(Tiphia femorata excluded as it is parasitic on non-aculeate species) Aerial Nester Frequency The aerial-nester frequency (AF) is the percentage of host aculeate species that have aerial nest sites. Aerial nesters use old beetle burrows in dead wood, central plant stem cavities (e.g. bramble), old snail shells, or crevices in old mortar or exposed on the surface of rock or other hard material. Subterranean nesters nest in the soil, usually in burrows dug by themselves, or sometimes holes and crevices are used after being altered. The AFs for the solitary species are given in Table 7. The AFs for all the British species of solitary wasps is 46·2% and for solitary bees is 17·9%. The AFs for the solitary wasp species is much lower than the national AF while the AFs for the solitary bee species are only slightly lower than the national AF. The low AFs for the solitary wasp species emphasizes the importance of bare sandy areas as nesting sites, although the extremely low value for West Stow C.P. is partly a consequence of the survey being mainly confined to the car park where aerial nesting sites were less available.
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Table 7. The nesting habits of host species of solitary wasps and bees recorded from Rampart Field and West Stow Country Park No. Aerial Nesters (A)
No. Subterranean Nesters (S)
Aerial Nester Frequency AF = 100 × A/(A+S)
Solitary Wasps Rampart Field West Stow C.P.
6 1
24 21
20·0 4·5
Solitary Bees Rampart Field West Stow C.P.
4 4
24 22
14·3 15·4
Social wasp species and bumble bees are usually subterranean nesters, although the nest of Bombus pratorum has been found in aerial situations such as old bird nests. Summary Rampart Field: 1. is an important East Anglian site with 85 recorded species of aculeate wasps and bees, of which 17 species are of national importance 2. has a species quality score that might be expected of the best inland sandy sites in East Anglia 3. has a tentative species-richness estimate of 110 solitary species, of which about 70% have been recorded 4. has the expected number of solitary species for the area of the site as found in the best inland sandy sites for south-east England 5. has solitary and bee cleptoparasitic loads similar to other sites as predicted by Wcislo (1987) 6. has a low aerial-nester frequency for solitary wasp species indicating the importance of the bare sandy areas as nesting sites References Archer, M. E. (1999). The aculeate wasps and bees (Hymenoptera: Aculeata) of the Ainsdale-Formby sand dines on the Lancashire coast compared with other northern sites. Br. J. Ent. Nat. Hist., 12: 1–10. Archer, M. E. (2002). The Wasps, Ants and Bees of Watsonian Yorkshire. Yorkshire Naturalists’ Union, York. Archer, M. E. (2004). The wasps and bees (Hymenoptera: Aculeata) of Roydon Common in Watsonian West Norfolk. Trans. Norfolk Norwich Nat. Soc., 37: 32–45. Archer, M. E. & Edwards, M. (2002). The aculeate Hymneoptera of Ambersham and Iping (with Stedham) Commons in West Sussex, including statistical procedures for estimating species richness. Br. J. Ent. Nat. Hist., 15: 91–103.
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Colwell, R. K. & Coddington, J. A. (1994). Estimating terrestrial biodiversity through extrapolation. Phil. Trans. R. Soc. Lond. B. 345: 101–118. Falk, S. (1991). A review of the scarce and threatened bees, wasps and ants of Great Britain. Research and Survey in Nature Conservation 35: 1–344. Heltshe, J. F. & Forrester, N. E. (1983). Estimating species richness using the Jackknife Procedure. Biometrics 39: 1–11. Kloet, G. S. & Hincks, W. D. (1978). A check list of British Insects. Part 4: Hymenoptera, revised by Fitton, M. G. et al. Handks. Ident. Br. Insects 11 (4): 1–159. Shirt, D. B. (ed.) (1987). British Red Data Books: 2. Insects. Nature Conservancy Council, Peterborough. Wcislo. W. T. (1987). The role of seasonality, host synchrony, and behaviour in the evulotions and distributions of nest parasites in Hymenoptera (Insecta), with special reference to bees (Apoidea). Biol. Rev. 62: 515–543. Appendix RF, Rampart Field. WS, West Stow C.P. Species statuses: Very rare (VR), Rare (R), Scarce (S), Restricted (RE), Widespread (W), Universal (U). Chrysididae Elampus panzeri (Fab.) RF, W. Hedychridium ardens (Latreille in Coquebert) RF. WS. U. H. roseum (Rossi) RF, WS, U. Chrysis ignita (L.) WS. U. C. impressa Schenck. RF. WS. U. C. illigeri (Wesmael) WS. S. Trichrysis cyanea (L.) WS. U. Tiphiidae Tiphia femorata Fab. RF. WS. S. Pompilidae Priocnemis parvula Dahlbom RF. U. Pompilus cinereus (Fab.) RF. U. Ageniodeus cinctellus (Spinola) WS. W. Episyron rufipes (L.) RF. WS. U. Anoplius infuscatus (Vander Linden). WS. W. A. viaticus (L.) RF. WS. S. Arachnospila trivalis (Dahlbom). WS. W. Evagetes crassicornis (Shuckard) RF. U. E. dubius (Vander Linden). RF. R. Eumeninae Ancistrocerus parietinus (L.) RF. U. A. trifasciatus (Müller) RF. U. Microdynerus exilis ( Herrich-Schäffer) WS. S. Vespinae Vespula rufa (L.) RF. Paravespula germanica WS. P. vulgaris (L.) RF. WS. Sphecidae Astata boops Latreille. RF. WS. RE. Dryudella pinguis (Dahlbom) WS. U. Tachysphex pompiliformis (Panzer) WS. U. Crabro cribrarius (L.) RF. U. C. peltarius (Schreber) RF. U. Crossocerus cetratus (Shuckard) RF. W. C. pusillus Lepeletier & Brullé RF. WS. U. C. quadrimaculatus (Fab.) RF. W. C. tarsatus (Shuckard). WS. U. C. wesmaeli (Vander Linden) RF. WS. U. Ectemnius continuus (Fab.) RF. WS. U. E. dives (Lepeletier & Brullé) RF. S. Lindenius albilabris (Fab.) RF. U. Entomognathus brevis (Vander Linden) WS. W. Oxybelus argentatus Curtis RF. S. O. uniglumis (L.) RF. WS. U. Mimesa equestris (Fab.) RF. U. M. lutaria (Fab.) RF. W. Diodontus minutus (Fab.) RF. WS. W. D. tristis (Vander Linden) RF. WS. S. Passaloecus gracilis (Curtis) RF. W. Ammophila sabulosa (L.) RF. WS. W. Podalonia affinis (Kirby) RF. WS. R. P. hirsuta (Scopoli) WS. S. Mellinus arvensis (L.) RF. U.
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Nysson spinosus Jurine WS. S. Cerceris arenaria (L.) RF. WS. W. C. quinquefasciata (Rossi) RF. VR. C. rybyensis (L.) RF. RE. Philanthus triangulum (Fab.) RF. WS. W. Colletinae Colletes daviesanus Smith. WS. U. C. fodiens (Geoffroy in Fourcroy) RF. WS. W. C. succinctus (L.) RF. WS. U. Hylaeus annularis (Kirby) RF. WS. RE. H. brevicorne Nylander WS. W. H. confusus Nylander RF. U. H. hyalinatus Smith. WS. W. Andreninae Andrena barbilabris (Kirby) RF. WS. U. A. bicolor Fab. RF. WS. U. A. denticulata (Kirby) WS. U. A. dorsata (Kirby) RF. WS. W. A. fulva (Müller in Allioni) WS. U. A. fuscipes (Kirby) RF. U. A. haemorrhoa (Fab.) RF. WS. U. A. humilis Imhoff RF. S. A. nigroaenea (Kirby) RF. U. A. ovatula (Kirby) RF. W. A. scotica Perkins WS. U. A. subopaca Nylander WS. U. A. tibialis (Kirby) WS. S. Halictinae Halictus confusus Smith RF. VR. H. rubicundus (Christ) WS. U. H. tumulorum (L.) WS. U. Lasioglossum brevicorne (Schenck) RF. WS. S. L. calceatum (Scopoli) RF. WS. U. L. leucopus (Kirby) RF. WS. U. L. leucozonium (Schrank) RF. WS. W. L. minutissimum (Kirby) RF. W. L. morio (Fab.) WS. W. L. parvulum (Schenck) RF. W. L. punctatissimum (Schenck) RF. W. L. quadrinotatum (Kirby) RF. WS. R. L. villosulum (Kirby) RF. WS. U. Sphecodes ephippius (L.) RF. W. S. monilicornis (Kirby) RF. WS. U. S. pellucidus Smith RF. WS. W. S. puncticeps Thomson RF. W. S. reticulatus Thomson RF. S. Melittidae Melitta haemorrhoidalis (Fab.) RF. S. Dasypoda hirtipes (Fab.) RF. S. Megachilinae Osmia leaiana (Kirby) RF. W. O. rufa (L.) WS. U. Hoplitis claviventris (Thomson) RF. W. Megachile dorsalis Pérez (=M. leachella) RF. WS. S. M. versicolor Smith RF. U. Coelioxys concoidea (Illiger) RF. S. Anthophorinae Nomada flava Panzer RF. W. N. ruficornis (L.) RF. U. N. rufipes Fab. RF. U. Epeolus cruciger (Panzer) RF. W. E. variegatus (L.) RF. WS. W. Apinae Bombus lapidarius (L.) RF. WS. B. lucorum (L.) RF. WS. B. hortorum (L.) WS. B. pascuorum (Scopoli) RF. WS. B. pratorum (L.) RF. WS. B. terrestris (L.) RF. B. campestris (Panzer) WS. B. vestalis (Geoffroy in Fourcroy) RF. WS. Apis mellifera L. RF. WS. Dr M. E. Archer 17 Elmfield Terrace Malton Road York YO31 1EH
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