Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-07T08:34:19.576Z Has data issue: false hasContentIssue false
  • English
  • Français

Distributional patterns of raptors along altitudinal gradients in the northern Andes and effects of forest fragmentation

Published online by Cambridge University Press:  10 July 2009

Jean-Marc Thiollay
Jean-Marc Thiollay
Affiliation:
Laboratoire d'Ecologie, Ecole Normale Supérieure, CNRS-URA 258, 46, rue d'Ulm, 75230 Paris, Cedex 05, France
Get access Rights & Permissions [Opens in a new window]

Abstract

A survey of the diurnal raptor community (46 resident species) at five altitudinal levels from 100 to 4600 m was made in Venezuela using 106 1-km2 sample quadrats and then compared with similar censuses (211 plots) in southwestern Colombia and eastern Ecuador. Six habitat types were defined and habitat preferences were measured from every encountered birds and from the association between individual abundances and the coverage of habitat types on plots. The overall species richness steeply declined with elevation in all three countries. The raptor community consisted mostly of tropical species that rapidly decreased in both abundance and frequency of occurrence with elevation. A small set of subtropical-temperate forest specialists partly replaced them at mid-elevation and only two species occurred in the paramo of Venezuela, against 5–7 in the other countries. Although originally the gradients were probably almost completely covered with forest, a large part of the raptor community is now composed of grassland species, three of them extending from the lowlands to the tree line. The relative impoverishment of the Venezuelan community, especially at upper levels, is attributed to a peninsular effect at the narrow extreme northern tip of the Andes and perhaps also to former forest fragmentation. Within some species, different subspecies had discrete altitudinal distributions and interspecific competition may explain differences in the range extension of some species between countries. Today, however, accelerating deforestation may result in a severe decline of forest-interior species and a probable reduction in the altitudinal range of at least some of them. Species naturally associated with forest gaps or edges usually tolerate a high degree of forest fragmentation and degradation but only one of them may become abundant in heavily human-altered woodlands. Few grassland specialists have become more widely distributed in the increasingly deforested landscapes.

Keywords

Andeselevationforest fragmentationgradienthabitat selectionraptorsspecies richness
Type
Research Article
Information
Journal of Tropical Ecology , Volume 12 , Issue 4 , July 1996 , pp. 535 - 560
Copyright
Copyright © Cambridge University Press 1996

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

LITERATURE CITED

Able, K. P. & Noon, B. R. 1976. Avian community structure along elevational gradients in the north eastern United States. Oecologia 26:275–294.CrossRefGoogle Scholar
Alvarez Del Real, M. E. (ed.) 1983. Atlas of Venezuela. Distribucion Escolar, Caracas, 320 pp.Google Scholar
Blake, E. R. 1977. Manual of Neotropical birds. University of Chicago Press, Chicago, 674 pp.Google Scholar
Butler, T. Y. 1979. The birds of Ecuador and the Galapagos archipelago. Ramphastos Agency, Portsmouth, N. H.68 pp.Google Scholar
Chapman, F. M. 1917. The distribution of bird life in Colombia. Bulletin of the American Museum of Natural History 36:1–169.Google Scholar
Chapman, F. M. 1926. The distribution of bird life in Ecuador. A contribution to a study of the origin of andean bird life. Bulletin of the American Museum of Natural History 55:1–784.Google Scholar
Collar, N. J., Gonzaga, L. P., Krabbe, N., Madrononieto, A., Naranjo, L. G., IIParker, T. A. & Wege, D. C. 1992. Threatened birds of the Americas. ICBP/IUCN Red Data Book. Smithsonian Institution Press. 1150 pp.Google Scholar
Fjeldsa, J. & Krabbe, N. 1990. Birds of the High Andes. Apollo Books, Svendborg, Denmark. 876 pp.Google Scholar
Fuller, M. R. & Mosher, J. A. 1987. Raptor survey techniques. Pp. 37–66 in Pendleton, B. A. Giron, Millsap, B. A., Kline, K. W. and Bird, D. M. (eds) Raptor management techniques manual. National Wildlife Federation, Washington D.C.420 pp.Google Scholar
Graham, G. L. 1990. Bats versus birds: comparisons among Peruvian flying vertebrate faunas along an elevational gradient. Journal of Biogeography 17:657–668.CrossRefGoogle Scholar
Haffer, J. 1974. Avian speciation in tropical South America. Publications Nuttall Ornithological Club 14. Cambridge, Mass.390 pp.Google Scholar
Hanski, I. 1978. Some comments on the measurement of niche metrics. Ecology 59:168–174.CrossRefGoogle Scholar
Hilty, S. L. and Brown, W. L. 1986. A guide to the birds of Colombia. Princeton University Press, Princeton, New Jersey. 836 pp.Google Scholar
Holdridge, L. R. 1967. Life zone ecology. Tropical Science Center, San Jose, Costa Rica.Google Scholar
Jacobs, J. 1974. Quantitative measurement of food selection: a modification of the forage ratio and Ivlevs' electivity index. Oecologia 14:413–417.CrossRefGoogle Scholar
Levins, R. 1968. Evolution in changing environments: some theoretical explorations. Princeton University Press, Princeton, New Jersey.CrossRefGoogle Scholar
Loiselle, B. A. & Blake, J. G. 1991. Temporal variation in birds and fruit along an elevational gradient in Costa Rica. Ecology 72:180–193.CrossRefGoogle Scholar
Meyer De Schauensee, R. & Phelps, W. H. 1978. A guide to the birds of Venezuela. Princeton University Press, Princeton, New Jersey. 424 pp.Google Scholar
Monasterio, M. (ed.) 1980. Estudios ecologicos en los Paramos Andinos. Ediciones Universidad de los Andes, Merida. 312 pp.Google Scholar
Navarro, A. G. S. 1992. Altitudinal distribution of birds in the Sierra Madre del Sur, Guerrero, Mexico. Condor 94:29–39.Google Scholar
Neu, L. W., Byers, C. R. & Peek, J. M. 1974. A technique for analysis of utilization-availability data. Journal of Wildlife Management 38:541–545.CrossRefGoogle Scholar
Noon, B. R. 1981. The distribution of an avian guild along a temperate elevational gradient: the importance and expression of competition. Ecological Monographs 51:105–124.CrossRefGoogle Scholar
Patterson, B. D. & Atmar, W. 1986. Nested subsets and the structure of insular mammalian faunas and archipelagoes. Biological Journal of Linnean Society 28:65–82.CrossRefGoogle Scholar
Peck, S. B. & Kukalova-Peck, J. 1980. A guide to some natural History field localities in Ecuador. Studies on Neotropical Fauna and Environment 15:35–55.CrossRefGoogle Scholar
Remsen, J. V. 1985. Community organization and ecology of birds of high elevation humid forest of the Bolivian Andes. Pp. 733–756 in Buckley, P. A. et al. (ed.). Neotropical ornithology. American Ornithologists' Union.Google Scholar
Roughgarden, J. 1989. The structure and assembly of communities. Pp. 203–226 in Roughgarden, et al. (eds), Perspectives in ecological theory. Princeton University Press, Princeton, New Jersey.CrossRefGoogle Scholar
Sarmiento, G., Monasterio, M., Azocar, A., Castellano, E. & Silva, J. 1971. Estudio integral de la Cuenca de los Rios Chama y Capazon. Vegetation natural. Institute de Geographia y Conservation de Recursos Naturales, Universidad de los Andes, departamento de Biologia, Merida. 65 pp.Google Scholar
Stevens, G. C. 1992. The elevational gradient in altitudinal range: an extension of Rapoport's latitudinal rule to altitude. American Naturalist 140:893–911.CrossRefGoogle ScholarPubMed
Terborgh, J. 1971. Distribution on environmental gradients: theory and a preliminary interpretation of distributional patterns in the avifauna of the Cordillera Vilcabamba, Peru. Ecology 52:23–40.CrossRefGoogle Scholar
Terborgh, J. 1977. Bird species diversity on an Andean elevational gradient. Ecology 58:1007–1019.CrossRefGoogle Scholar
Terborgh, J. 1985. The role of ecotones in the distribution of Andean birds. Ecology 66:1237–1246.CrossRefGoogle Scholar
Terborgh, J. & Weske, J. S. 1975. The role of competition in the distribution of Andean birds. Ecology 56:562–576.CrossRefGoogle Scholar
Thiollay, J. M. 1989. Area requirements for the conservation of rain forest raptors and game birds in French Guiana. Conservation Biology 3:128–137.CrossRefGoogle Scholar
Thiollay, J. M. 1991. Altitudinal distribution and conservation of raptors in south western Colombia. Journal of Raptor Research 25:1–8.Google Scholar
Thiollay, J. M. 1993. Response of a raptor community to shrinking area and degradation of tropical rain forest in the south western Ghâts (India). Ecography 16:91–110.CrossRefGoogle Scholar
Vuilleumier, F. 1970. Insular biogeography in continental regions. I. The northern Andes of South America. American Naturalist 104:377–388.CrossRefGoogle Scholar
Vuilleumier, F. 1984. Zoogeography of Andean birds: two major barriers, and speciation and taxonomy of the Diglossa carbonaria superspecies. National Geographic Society Research Report 16:713–731.Google Scholar
Vuilleumier, F. 1986. Origins of the tropical avifaunas of the high Andes. Pp. 586–622 in Vuilleumier, F. & Monasterio, M. (eds), High altitude tropical biography. Oxford University Press, New York. 649 pp.Google Scholar
Vuilleumier, F. & Ewert, D. N. 1978. The distribution of birds in Venezuelan paramos. Bulletin of the American Museum of Natural History 162:49–90.Google Scholar
Vuilleumier, F. & Monasterio, M. (eds) 1986. High altitude tropical biogeography. Oxford University Press, New York. 649 pp.Google Scholar