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DISJUNCT BIRD DISTRIBUTIONS ALONG THE WEST SLOPE OF THE PERUVIAN ANDES IRMA FRANKE Museo de Historia Natural, Universidad Nacional de San Marcos, Casilla 14-0434, Lima 14, Peru

ABSTRACT. Within the steppe-like western slope ol the Peruvian Andes lores! patches (dry cloud lores!) occur lrom Ecuador to 13º8. Eight siles were studied between Huamba and Zárate. A total ol 124 taxa were used to analyze disjunctions. Species numbers decrease from N to S along a gradient of decreasing rainlall. Group 1 taxa (102 species and subspecies) occur from Ecuador south. Nine distributional limits exist. Group 2 taxa (22 species and subspecies) include endemics. Five areas of taxon replacement were identified. The major replacement area is near the Rio Santa Valley. Birds now living in dry cloud lorests along the western Andes originated north of this region. Distribution gaps have played an Importan! role in the history of the taxa.

Keywords: Zoogeography, disjunction, Andes, dry cloud lorests, Peru.

INTRODUCTION

The Pacific slope of the Peruvian Andes is dominated by arid, steppe-like vegetation types. However, many small forest patches occur in this dry zone between 2400 and 3000 m, forming the richest communities of the western slope of the Peruvian Andes (Koepcke, H.W. 1961, Valencia & Franke 1980, Franke & Valencia 1984). In northern Peru these dry cloud forests occupy extensive and relatively continuous areas, but further south they occur in increasingly smaller and more isolated patches, to about 13ºS (Koepcke, H.W. 1961, Valencia 1990). These disjunct forests are thought to represent fragments of a formerly more continuous forest zone (Koepcke, M. 1958; Koepcke, H.W. 1961 ).

The floristic and faunistic affinities between west slope and east slope forests, as well as the existence of low passes in northern Peru, especially the Porculla Pass (2145 m), led to the hypotheses that east slope species (1) crossed the low passes to the west, and (2) dispersed southward through the forest belt (Koepcke, M. 1958, 1961 b, Koepcke, H.W. 1961, Simpson 1975). Biogeographers accept the idea that the Andean montane forests were more continuous when depressed altitudinally during cool, humid glacial periods. At such times temperate and subtropical zones were located along less dissected lower slopes. Conversely, the upward shift of climatic zones during interglacial periods led to increasing fragmentation of montane vegetation (Haffer 1987), thus isolating bird populations and playing a role in speciation along the western Peruvian Andes.

METHODS

Field studies were made at 8 dry cloud forest sites between 2500 and 3000 m, from 4º41 'S, near the Ecuadorian border, to 11 º55'S in central Peru: (1) Huamba, Department of Piura (4º41 'S, 2900 m); (2) Chiñama, Lambayeque (6º06'S, 2550 m); (3) Llaguén, La Libertad (7º42'S, 2600 m); (4) Cochabamba, Ancash (9º27'S, 2800 m);

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(5) Wiñapajatun, Ancash {9º41 'S, 2600 m); (6) Noqno, Ancash (10º03'S, 2850 m); (7) Linday, Lima (11 º50'S, 3000 m), and (8) Zárate, Lima {11 º55'S, 2850 m).

Distributional records of the species observed at the 8 sites (Appendix 1) are based on the author's field work, museum specimens (Museo de Historia Natural, Universidad de San Marcos, Lima; Louisiana State University Museum of Natural History, Baton Rouge; National Museum of Natural History, Washington; Field Museum of Natural History, Chicago; and British Museum of Natural History, Tring), and the literature (Koepcke M. 1958, 1961 a, b, 1965, Valencia & Franke 1980, Franke & Valencia 1984, Hellmayr, Conover & Cory 1918-1949, Zimmer 1931-1975, Fjeldsa & Krabbe 1990, Parker et al. 1985, Meyer de Schauensee 1966, Schulenberg 1987, Schulenberg & Parker 1981, Parker 1981, O'Neill & Schulenberg 1979, Plenge 1974).

For each species the records were plotted on a map of the study area in order to determine the latitudinal limits of each species.

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After eliminating low altitude species that reach the dry cloud forests only occasionally, a list of 128 species was obtained. For 9 of these species only scattered records exist and these specles were eliminated. In several of the 119 remaining species, more than one subspecies occur in the study area. Given relatively minor differences between most subspecies, geographic variation may actually be clinal. Since subspecies present difficulties in biogeographic analysis (Cracraft 1985) they were avoided, with one exception. Four species have morphologlcally distinct subspecies ranging along the latitudinal gradient studied: Cranioleuca antisiensis (3 subspecies), Aglaeactis cupripennis (2), Lepthastenura pileata (2) and Atlapetes seebohmi (2). In spite of Cracraft's (1985) caveat 1 have included the subspecies of these tour species because they are well marked and present interesting distributional information. Thus, 124 taxa {116 species and 8 subspecies) were analyzed in the present paper.

RESULTS

The number of species in dry cloud forests decreases markedly from north to south, from 102 species in northwestern Peru to 56 in central Peru (Figure 1). The N - S decrease in species numbers is significantly correlated (r=0.8723, P>0.001) with the gradient of decreasing rainfall. In turn vegetation characteristics of the dry cloud forests reflect the rainfall gradient (Valencia 1990).

The 124 laxa are divided into two groups. In the first group 1 place 102 laxa that occur in Ecuador and have a continuous or nearly continuous distribution southward to a certain point along the western slope. In the second group (22 taxa) 1 include species and subspecies that do not occur in Ecuador, but have a continuous or relatively continuous distribution along part of the western slopes (Appendix 1).

DISTRIBUTION PATTERNS OF GROUP 1 TAXA

The 102 laxa in group 1 can be divided into nine subgroups, with southern limits at the following areas: (1) Porculla Pass (7 laxa, 5º51 'S); (2) Chiñama (7 taxa, 6º06'S); (3) Rio Chancay Valley (4 taxa, 6º40'S); (4) Rio Saña Valley (26 taxa, 6º54'S); (5) Rio Jequetepeque Valley (2 taxa, 7°19'S); (6) Rio Chicama Valley (4 taxa, 7°29'S);

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(7) Llaguén (8 taxa, 7º42'); (8) Cordilleras Blanca and Negra (5 taxa, ca. 1OºS); (9) 39 taxa occurring at the southern limit of the study area (11 º55'S) but not necessarily having their southern distributional limit there.

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A plot of numbers of taxa in group 1 against latitude shows a N - S decreasing trend (Figure 1). This trend is highly correlated with the rainfall gradient (r= 0.9128, P<0.001) and very similar to the trends obtained for vegetation parameters (number of woody species, density, basal area and vertical structure; Valencia 1990). These results strongly suggest that climate and habitat conditions are important factors in these distributions patterns.

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DISTRIBUTION PATTERNS OF GROUP 2 TAXA

The second group consists of 22 taxa including species endemic to western Peru, several of which have a very restricted distribution. Nine subgroups of closely related taxa replace each other latitudinally along the study area (Figure 2). Three of these subgroups consist of subspecies: Cranio/euca antisiensis (3 subspecies), Lepthastenura pileata (2) and Aglaeactis cupripennis (2). Three subgroups consist of species that are often treated as subspecies: Anairetes nigrocristatus and A. reguloides, Saltator nigriceps and S. aurantiirostris, and Atlapetes seebohmi and A. nationi. Finally, the last three subgroups consist of congeneric species: Synallaxis elegantior and S. zimmeri, Ochthoeca piurae and O. leucophrys, and Diglossa humera/is and D. brunneiventris. Only two of these subgroups show distributional overlap (Anairetes and Ochthoeca species), where the deep Rio Santa Val ley separates the Cordilleras Blanca and Negra.

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FIGURE 2 - Latitudinal distribution of nine groups of related taxa that replace each other along the western slope of the Peruvian Andes. Abbreviations: Ann, Anairetes nigrocristatus; Anr, A. reguloides; Op, Ochthoeca piurae; 01, O. leucophrys; Cap, Cranioleuca antisiensis palamb/ae; Cab, C. a. baroni; Caz, C. a. zaratensis; Acp, Aglaeactis cupripennis parvulus; Acc, A. c. caumatonotus; Lpc, Lepthastenura pileata cajabambae; Lpp, L. p. pi/eata; Dh, Diglossa humera/is; Db, D. brunneiventris; Ass, Atlapetes seebohmi seebohmi; An, Atlapetes nationi, Sn, Saltator nigriceps; Sa, S. aurantiirostris; Se, Synallaxis e/egantior; Sz, S. zimmeri. Shaded areas: majar areas of species or subspecies replacement.

Five major areas of species or subspecies replacement or range limits (Figure 2) are listed below.

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Around 5º20'S, near El Tambo, Piura; northern limit of Anairetes nigrocristatus and Ochthoeca piurae.

(2) Around 6º30'S, near Llama and Chugur, Cajamarca, deep valley of Ria Chancay (upper Ria Reque); contact between Diglossa humera/is and D. brunneiventris (Graves 1982, Vuilleumier 1984). replacement of Saltator nigriceps by S. aurantiirostris and Cranioleuca antisiensis palamblae by e.a. baroni.

(3) Around 7º30'S, near Huacraruco, Sunchubamba and Llaguén, deep valleys of Rios Jequetepeque and Chicama; replacement of Synallaxis elegantior by S. zimmeri, southern limit of Aglaeactis cupripennis parvulus, northern limit on the western slope of Atlapetes seebohmi seebohmi, Lepthastenura pileata cajabambae, Anairetes reguloides, Polyonymus caroli, and Chrysoptilus atricollis.

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(4) Between 8ยบ30' and 9ยบS, Rio Santa Valley. Area no. 4 is particularly important. The Rio Santa is the largest river of the Pacific watershed and forms the largest valley of western Peru. The upper Rio Santa, running for 180 km parallel to the coast before turning westward separates the eastern and very high Cordillera Blanca from the western, lower Cordillera Negra. Avian distribution patterns in this area are complex.

Most species occurring north of the Rio Santa Valley have a relatively extensive range and are present in both the Cordilleras Blanca and Negra. A few species, however, have only been reported from the Cordillera Blanca (e.g. Mecocerculus leucophrys, Ochthoeca rufipectora/is). Four of the groups of taxa (see above) show replacement or separation in the Rio Santa Valley. (1) Northerly Anairetes nigrocristatus occurs in the Cordillera Blanca, whereas southerly A. reguloides occurs in the Cordillera Negra. There is only one possible record of regu/oides from the Cordillera Blanca (Frimer & Nielsen 1989). (2) Cranioleuca antisiensis baroni (northerly), occurs only in the Cordillera Blanca, whereas C. a. zaratensis (southerly), occurs in the Cordillera Negra. Fjeldsa and Krabbe (1990:358-359) consider baroni a full species. They further state that C. baroni baroni "crosses to Pacific slope of Cordillera Negra" in Ancash. However, the 9 specimens collected during my study in the Cordillera Negra (Ancash) have the same characters as the 1O specimens of zaratensis from the Department of Lima and not the characters of baroni. (3) Aglaeactis cupripennis caumatonotus occurs on both cordilleras, but has not been recorded on the western slope north of the Santa Valley, where the specimens available correspond to A. c. parvulus. (4) Ochthoeca piurae and O. leucophrys are sympatric in the Cordillera Negra, but the latter species also occurs in the Cordillera Blanca. lt is noteworthy that Synallaxis zimmeri, like O. piurae an endemic species restricted to a small area of the Pacific slope, occurs along the Cordillera Negra and further north in Lambayeque. These taxa have not yet been recorded from Cordillera Blanca or any other locality within the Santa Valley.

(5) Around 10ยบ30'S, Rio Pativilca Val ley; replacement of Lepthastenura pileata cajabambae by L. p. pileata and Atlapetes seebohmi seebohmi by A. nationi; southern limit of Synallaxis zimmeri and Ochthoeca piurae .

DISCUSSION

Northern origin The distribution patterns described in this paper, especially the patterns of species replacement and/or species limits at given areas along the western slope of the Peruvian Andes, supports the concept of a northern origin for most avifaunal elements of dry cloud forests. The N - S decrease in species numbers is also correlated to the decrease in rainfall and associated vegetation parameters (number of woody species, density, basal area and vertical structure, Valencia 1990). Thus, historical as well as ecological factors have had important effects on avian distribution.

The complex distribution patterns found in Ancash also support the idea of a northern origin. lf the species dispersed from north to south, they would be expected to have occupied the appropriate habitats in the Rio Santa Valley, including the

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Cordillera Blanca, befare they dispersad to the Cordillera Negra. Several species with a southern limit in Ancash show this pattern, as do also the Cranioleuca and Anairetes groups. In these instances, the northern species (or subspecies) occupies the Cordillera Blanca, whereas the southern one occurs from the Cordillera Negra southward.

The distribution of Synallaxis zimmeri and Ochthoeca piurae does not correspond to this pattern, however. These 2 species occur north of the Santa Valley, in La Libertad and along the Cordillera Negra, but they are not recordad in the Santa Valley. The differences between the patterns in Cranioleuca and Anairetes on the one hand, and in S. zimmeri and O. piurae on the other, can be explained by the fact that species occupying the interior of the Santa Valley, Cordillera Blanca, range up to around 4000 m, whereas Synallaxis zimmeri and Ochthoeca piurae occur lower, from 15001800 m to about 2800 m. Both species occur in open, dry habitats as well as in dry cloud forests. lt is thus not surprising that these species did not reach the upper Santa Valley, but instead dispersad southward along the lower slopes.

Efficacy of barriers Although the efficacy of low passes in the western cordillera as barriers to dispersa! of montane species has been questioned (Parker et al. 1985), it is intriguing to note that many range limits coincide with areas where the western Andes are lowest (Vuilleumier 1969, 1977) and with the deepest valleys of the Pacific drainage. This distribution gap could be an artifact resulting from incompleta sampling in the area.

Only further investigation will resolve this issue unequivocally. However, a study of the distribution of 306 dry cloud forest patches shows that several important latitudinal gaps coincide with the low areas of the western Andes and with the deep valleys of the Pacific slope (Valencia 1990). lf montana farests were more continuous in the past during cool and humid glacial periods, when they occupied the lower, more continuous mountain slopes, then the low passes and the deep valleys must have played an important role in fragmenting the forest zone as it shifted upward during interglacial periods. The increasing patchiness of the forest resultad probably not only from the more complex topography of the upper slopes (Haffer 1987), but also from the retreat of farest patches to favorable slopes. Valencia (1990) has shown the tendency of forest patches to be restricted to more humid slopes. The low passes must also have had an effect in dissecting the forest area. As mentioned earlier, dry cloud farests occur generally between 2400 and 3000 m. Summits in the low Andes of northwestern Peru are below 3000 m, thus restricting considerably the potential extension of forest. Vuilleumier (1969, 1977, 1984) presentad models of the effects of the Pleistocena depression in northern Peru.

Main gaps Three gaps are especially important. The first gap, between 6º30' and 6º47'S, corresponds to the Ria Chancay (upper Ria Reque) Valley, Cajamarca, where the western Andes are low and narrow. The contact between Diglossa humera/is and Diglossa brunneiventris is found here (Graves 1982, Vuilleumier 1984). Koepcke (1961 b) and Zimmer (1942) considerad the low pass in this area to be the dispersa! route by which Cranioleuca antisiensis baroni and Cyclarhis gujanensis reached the western slope.

This area may have been more importan! far dispersa! and speciation of birds than the Porculla Pass. Even though Porculla is the lowest pass in northwestern Peru, it occurs in a relatively linear area of the western Andes, thus presenting no special

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problem for dispersa! (Vuilleumier 1984 discussed the barrier effect of the Porculla Pass and surrounding areas).

The second gap, between 8º28' and 8º49'S, correponds to the Rio Santa Valley and is wide (about 50 km). This val ley separates Cranioleuca antisiensis baroni from C. a. zaratensis, and Anairetes nigrocristatus from Anairetes reguloides. In both cases the northern taxon occurs in the Cordillera Blanca, while the southern one is distributed from the Cordillera Negra southward.

The third gap, between 10º30' and 10º45'S, corresponds to the Rio Pativilca Valley.

This val ley separates two pairs of taxa, Lepthastenura pileata cajabambae from L. p. pileata, and Atlapetes seebohmi seebohmi from Atlapetes nationi, and marks the southern limit of west slope endemics, Ochthoeca piurae and Synallaxis zimmeri.

ACKNOWLEDGEMENTS 1 thank Karl-L. Schuchman and F. Vuilleumier for their invitation to participate in this symposium. Attendance at the 1.0.C. was made possible by a special travel grant to F. Vuilleumier, a grant from the American Ornithologists Union, and assistance from the organizers of the 20th 1.0.C. 1 am thankful to M.L.Gorman for his advice. For permitting me to examine specimens under their care and providing other courtesies, 1 am grateful to J. O'Neill and V. Remsen of Louisiana State University Museum of Natural History; J. Fitzpatrick and S. Lanyon of the Field Museum of Natural History; M. Foster of the National Museum of Natural History and A. Knox and P. Colston of the British Museum of Natural History. Field work was supported by the Frankfurt Zoological Society (project 905/81) and the Consejo Nacional de Ciencia y Tecnologia (CONCYTEC) of Peru.

LITERATURE CITED CRACRAFT, J. 1985. Historical biogeography and patterns of differentiation within the South American avifauna: areas of endemism. Pp 49-84 in Buckley, P.A., Foster, M.S., Morton, E.S., Ridgely, R.S., Buckley, F.G. (Eds). Neotropical Ornithology, Ornithological Monographs No. 36, Washington, D.C., American Ornithologists' Union.

FJELDSÁ, J., KRABBE, N. 1990. Birds of the High Andes. Zoological Museum, University of Copenhagen.

FRANKE, l., VALENCIA, N. 1984. Zarate: una unidad de conservacion. Report. Museo de Historia Natural, Universidad Nacional Mayor de San Marcos.

FRIMER, O., NIELSEN, S.M. 1989. The status of Poly/epis forests and their avifauna in Cordillera Blanca, Peru. Technical report from an inventory in 1988, with suggestions for conservation management. Copenhagen.

GRAVES, G.R. 1982. Speciation in the Carbonated flower-piercer (Dig/ossa carbonaria) complex of the Andes. Condor 84:1-14.

HAFFER, J. 1987. Quaternary history of tropical America. Pp 1-18 in Whitmore, T.C., Prance, G.T. (Eds). Biogeography and Quaternary History in Tropical America. Oxford: Claredon Press.

HELLMAYR, C.E., CONOVER, B. CORY, C.B. 1918-1949. Catalogue of birds of the Americas. 11 vols.

Chicago: Field Museum of Natural History Publications 197; 223; 242; 266; 330; 347; 365; 381; 430; 514; 615; 616; 634.

KOEPCKE, H.W. 1961. Synoekologishe Studien an der Westseite der peruanischen Anden. Bonner Zoologischer Beitraege 29: 1-320.

KOEPCKE, M. 1958. Die Vogel des Waldes van Zárate (Westhang der Anden in Mittelperu). Bonner Zoologischer Beitraege 9: 130-193.

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KOEPCKE, M. 1961 a. Birds of the western slope of the Andes of Peru. American Museum Novitates N. 2028.

KOEPCKE, M. 1961b. Las razas geograficas de Cranioleuca antisiensis (FURNARllDAE, AVES), con la descripcion de una nueva subespecie. Publicaciones del Museo de Historia Natural "Javier Prado".

Ser. A. Zoología. No. 20.

KOEPCKE, M. 1965. Zur Kenntnis einiger Furnariiden (Aves) der Kuste und des westlichen Andenabhanges Perus. Beitrag zur Neotropischen Fauna IV:150-173.

MEYER DE SCHAUENSEE, R. 1966. The species of birds of South America and their distribution.

Narberth, Penn. Livingston Publishing Company.

O'NEILL, J.P., SCHULENBERG, T.S. 1979. Notes on the Masked Saltator, Saltator cinctus, in Peru.

Auk 96:610-613.

PARKER, T.A.,111. 1981. Distribution and biology of the White-cheeked Cotinga Zaratornis stresemanni, a high Andean frugivore. Bulletin of the British Ornithologists' Club 101: 256-265.

PARKER, T.A., 111; SCHULENBERG, T.S.; GRAVES, G.R., BRAUN, M.J. 1985. The avifauna of the Huancabamba region, northern Peru. Pp. 169-197 in Buckley, P.A., Foster, M.S., Morton, E.S., Ridgely, R.S., Buckley, F.G. (Eds). Neotropical Ornithology, Ornithological Monographs No. 36, Washington, D.C., American Ornithologists' Union.

PLENGE, M.A. 1974. Notes on sorne birds in west-central Peru. Candor 76: 326-330.

SCHULENBERG, T.S. 1987. New records of birds from western Peru. Bulletin of the British Ornithologists' Club 107: 184-189.

SCHULENBERG, T.S., PARKER, T.A.,111. 1981. Status and distribution of sorne northwestern Peruvian birds. Candor 83: 209-216.

SIMPSON, B.B. Pleistocena changes in the flora of the high tropical Andes. Paleobiology 1: 273-294.

VALENCIA, N. 1990. Ecology of forests on the western slopes of the Peruvian Andes. Ph. D. Thesis.

Aberdeen University.

VALENCIA, N., FRANKE, l. 1980. El bosque de Zárate y su conservación. Boletín de Lima. 7: 76-86; 8: 26-35.

VUILLEUMIER, F. 1969. Pleistocena speciation in birds living in !he high Andes. Nature 223: 11791180.

VUILLEUMIER, F. 1977. Barrieres écogéographiques permettant la spéciation des oiseaux des hautes Andes. Pp. 29-51 in Descimon, H. (Ed. ). Biogéographie et évolution en Amérique tropicale Ecole Normale Superieure, París. Publications du Laboratoire de Zoologie, Numéro 9.

VUILLEUMIER, F. 1984. Zoogeography of Andean birds: two majar barriers; and speciation and taxonomy of the Diglossa carbonaria superspecies. National Geographic Society Research Reports 16: 713-731.

ZIMMER, J.T. 1931-1955. Studies o! Peruvian birds. American Museum Novitates 500, 509, 523, 524, 538, 545, 558, 584, 646, 647, 668, 703, 728, 753,756, 757, 785, 819, 860, 861, 862, 889, 893, 894, 917, 930, 962, 963, 994, 1042, 1043, 1044, 1045, 1066, 1095, 1108, 1109, 1126, 1127, 1159, 1160, 1168, 1193, 1203, 1225, 1245, 1246, 1262, 1263, 1304, 1345, 1367, 1380, 1428, 1449, 1450, 1463, 1474, 1475, 1513, 1540, 1595, 1604, 1609, 1649, 1723.

APPENDIX 1

Avian taxa recorded at 8 dry cloud forest sites along the western slope of the Peruvian Andes. Code number indicates distribution southward from Ecuador. (1) To Porculla Pass, 5º51 'S; (2) To Chiñama, 6º06'S; (3) To Ria Chancay Valley, 6º40'S; (4) To Ria Saña Valley, 6º54'S; (5) To Ria Jequetepeque Valley, 7°19'S; (6) To Ria Chicama Valley, 7º29'S; (7) To Llaguén, 7º42'S; (8) To Cordilleras Blanca and Negra, ca. 1OºS; (9) To Zárate, 11 º55'S. (1 O) Avian forms that do not occur in Ecuador; (11) Avían forms with scattered records from western Peru; (12) Low altitude species. Taxa are listed as species (family). * Migrant from North America; all other species are "resident".

Distribution pattern 1: Pipreo/a arcuata (Cotingidae). Myiotheretes fumigatus (Tyrannidae), Troglodytes solstitialis (Troglodytidae), Saltator cínctus (Cardinalidae), Hemispingus vertica/is (Thraupidae), Tragan personatus (Trogonidae), Cyanolyca turcosa (Corvidae).

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Distribution pattern 2: Geotrygon frenata (Columbidae), Pículus rívolíí (Picidae), Craníoleuca antísíensís pa/amblae (Furnariidae), Phyllomyías uropygía/ís (Tyrannidae), Elaenía pallatangae (Tyrannidae), Pachyramphus a/bogríseus (Cotingidae), Catamblyrhynchus diadema (Catamblyrhynchidae).

I

Distribution pattern 3: Diglossa humera/is (Coerebidae), Saltator nígríceps (Cardinalidae), Colibrí thalassínus (Trochilidae), Lafresnaya lafresnayí (Trochilidae).

Distribution pattern 4: Penelope barbata (Cracidae), Cíccaba a/bitarsus (Strigidae), Coelígena iris (Trochilidae), Ensífera ensífera (Trochilidae), Pharomachrus auríceps (Trogonidae), Lepídocolaptes affínís (Dendrocolaptidae), Margarornís squamiger (Furnariidae), Pseudocolaptes bíossonneautíí (Furnariidae), Automolus rufícollís (Furnariidae), Gral/aria rufícapílla (Formicariidae), Phyllomyías nígrocapillus (Tyrannidae), Mionectes striatícollis (Tyrannidae), Contopus fumígatus (Tyrannidae), Turdus serranus (Turdidae), Atlapetes leucopterus (Emberizidae), Atlapetes torquatus (Emberizidae), Tangara virídicollis (Thraupidae), Anísognathus lacrymosus (Thraupidae), Thraupís cyanocephala (Thraupidae), Hemíspíngus supercílíarís (Thraupidae), Díglossa cyanea (Coerebidae), Myíoborus melanocephalus (Parulidae), Basíleuterus coronatus (Parulidae), Conírostrum síttícolor (Coerebidae), Cyclarhís gujanensís (Vireonidae), Víreo gílvus (Vireonidae).

..

Distribution pattern 5: Accípíter stríatus (Accipitridae), Syna//axís e/egantíor (Furnariidae).

Distribution pattern 6: Mecocercu/us stíctopterus (Tyrannidae), *Catharus fuscater (Turdidae), Atlapetes rufinucha (Emberizidae), Tangara vassoríí (Thraupidae).

Distribution pattern 7: Adelomyía melanogenys (Trochilidae), Aglaeactís cuprípennís parvu/us (Trochilidae), He/íangelus viola (Trochilidae), Scytalopus unicolor (Rhinocryptidae), Hemíspíngus melanotís (Thraupidae), Myíoborus míníatus (Parulidae), Basí/euterus nígrocrístatus (Parulidae), Basíleuterus trífascíatus (Parulidae).

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Distribution pattern 8: Venílíornís fumígatus (Picidae), Turdus fuscater (Turdidae), Nyctídromus a/bícol/ís (Caprimulgidae), Mecocerculus leucophrys (Tyrannidae), Ochthoeca rufípectoralís (Tyrannidae).

Distribution pattern 9: Nothoprocta pentlandíí (Tinamidae), Geranoaetus melanoleucus (Accipitridae), Buteo polyosoma (Accipitridae), Falco sparveríus (Falconidae), Columba fascíata (Columbidae), Zenaída aurículata (Columbidae), Leptotíla verreauxí (Columbidae), Aratínga waglerí (Psittacidae), Glaucídíum jardiníí (Strigidae), Caprímulgus longírostrís (Caprimulgidae), Colibrí coruscans (Trochilidae), Patagona gigas (Trochilidae), Lesbia nuna (Trochilidae), Meta/fura tyríanthína (Trochilidae), Ampelion rubrocristatus (Cotingidae), Elaenía a/bíceps (Tyrannidae), Anaíretes parulus (Tyrannidae), Contopus cínereus (Tyrannidae), Ochthoeca jelskíí (Tyrannidae), Myíotheretes stríatícollís (Tyrannidae), Agríornís montana (Tyrannidae), Muscísaxícola maculírostrís (Tyrannidae), Myíarchus tuberculífer (Tyrannidae), Notíochelidon murína (Hirundinidae), Notiochelidon cyanoleuca (Hirundinidae), Cinclus /eucocephalus (Cinclidae), Troglodytes aedon (Troglodytidae), Turdus chíguanco (Turdidae), Zonotríchía capensís (Emberizidae), Phrygílus plebejus (Emberizidae), Catamenia analis (Emberizidae), Catamenía ínornata (Emberizidae), Pheuctícus chrysogaster (Cardinalidae), Thraupís bonaríensís (Thraupidae), Píranga flava (Thraupidae), Thlypopsis ornata (Thraupidae), Diglossa sittoídes (Coerebidae), Conírostrum cínereum (Coerebidae), Carduelís magellaníca (Carduelidae).

326

ACTA XX CONGRESSUS INTERNATIONALIS ORNITHOLOGICI

Distribution pattern 1O: Leptasthenura pileata pileata (Furnariidae), Atfapetes nationi (Emberizidae), Leptasthenura pileata cajabambae (Furnariidae), Synallaxis zimmeri (Furnariidae), Atlapetes seebohmi seebohmi (Emberizidae), Ochthoeca piurae (Tyrannidae), Aglaeactis cupripennis caumatonotus (Trochilidae), Cranioleuca antisiensis zaratensis (Furnariidae), Asthenes pudibunda (Furnariidae), Ampelion stresemanni (Cotingidae), Phrygilus fruticeti (Emberizidae), Poospiza rubecula (Emberizidae), Cranioleuca antisiensis baroni (Furnariidae), Polyonymus caroli (Trochilidae), Chrysoptilus atricollis (Picidae), Anairetes reguloides (Tyrannidae), Aeronautes andecolus (Apodidae), Meta/fura phoebe (Trochilidae), Saltator aurantiirostris (Cardinalidae), Diglossa brunneiventris (Coerebidae), Metriopelia ceciliae (Columbidae), Ochthoeca leucophrys (Tyrannidae).

Distribution pattern 11: Claravis mondetoura (Columbidae), Bolborhynchus orbygnesius (Psittacidae), Otus koepckeae (Strigidae), Otus sp (Strigidae), Aegolius harrissi (Strigidae), Uropsalis segmentata (Caprimulgidae), *Catharus ustulatus (Turdidae), Atlapetes seebohmi simonsi (Emberizidae), Pipraeidea melanonota (Thraupidae).

Distribution pattern 12: Columbina cruziana (Columbidae), Amazilia amazilia (Trochilidae), Thaumastura cora (Trochilidae), Myrtis fanny (Trochilidae), Picu/us rubiginosus (Picidae), Myiopagis subplacens (Tyrannidae), Euscarthmus meloryphus (Tyrannidae), Pachyramphus homochrous (Cotingidae), Campylorhynchus fasciatus (Troglodytidae), Turdus reevei (Turdidae), Poospiza hispaniolensis (Emberizidae), Paru/a pitiayumi (Parulidae), Dives warszewiczi (lcteridae).

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