Skip to main content
×
×
Home

Effects of habitat degradation on mixed-species bird flocks in Indian rain forests

  • Hari Sridhar (a1) and K. Sankar (a1)
Abstract:
Abstract:

Habitat degradation affects mixed-species bird flocks (flock hereafter) through two mechanisms – changes in the bird community from which flocks are drawn and changes in the propensities of species to flock. We determined the relative influence of these two mechanisms by examining variation in flocks across nine rain-forest fragments (range 11–2600 ha) in a plantation landscape in the Western Ghats, India. We found differences between fragments in average number of species (range 10.8–15.2) and individuals (range 19.0–37.6) per flock, number of species that participated in flocks (range 34–59), encounter rates (range 0.5–2.4 flocks h−1) and flock composition. Multiple regression and randomization tests revealed that different mechanisms contributed to this variation. Three flock variables (open-forest individuals per flock, total open-forest species that participated in flocks in a fragment, flock composition) mainly reflected changes in the bird communities of fragments. Habitat structure strongly influenced three flock variables (open-forest species per flock, total and rain-forest individuals per flock) and flock composition to a lesser extent. Finally, flock encounter rate was strongly related to fragment area, but not to abundance of flock participants indicating habitat degradation-induced changes in propensities of species to flock.

Copyright
Corresponding author
1Corresponding author. Current address: Centre for Ecological Sciences, Indian Institute of Science, Malleswaram, Bangalore – 560012, Karnataka, India. Email: hari@ces.iisc.ernet.in
References
Hide All
ACHARD F., EVA H. D., STIBIG H.-J., MAYAUX P., GALLEGO J., RICHARDS T. & MALINGREAU J.-P. 2002. Determination of deforestation rates of the world's humid tropical forests. Science 297:9991002.
ALI S. & RIPLEY S. D. 1983. Handbook of the birds of India and Pakistan (Compact edition). Oxford University Press, Delhi. 794 pp.
CHEN C.-C. & HSIEH F. 2002. Composition and foraging behaviour of mixed-species flocks led by the Grey-cheeked Fulvetta in Fushan Experimental Forest, Taiwan. Ibis 144:313330.
DANIELS R. J. R., JOSHI N. V. & GADGIL M. 1992. On the relationship between bird and woody plant species diversity in the Uttara Kannada district of south India. Proceedings of the National Academy of Sciences, USA 89:53115315.
DEBINSKI D. M. & HOLT R. D. 2000. A survey and overview of habitat fragmentation experiments. Conservation Biology 14:342355.
DEVELEY P. F. & PERES C. A. 2000. Resource seasonality and the structure of mixed species bird flocks in a coastal Atlantic forest of southeastern Brazil. Journal of Tropical Ecology 16:3353.
DOLBY A. S. & GRUBB T. C. 1998. Benefits to satellite members in mixed-species foraging groups: an experimental analysis. Animal Behaviour 56:501509.
DOLBY A. S. & GRUBB T. C. 1999. Functional roles in mixed-species foraging flocks: a field manipulation. Auk 116:557559.
FAHRIG L. 2003. Effects of habitat fragmentation on biodiversity. Annual Review of Ecology, Evolution and Systematics 34:487515.
FERNÁNDEZ–JURICIC E. 2000. Forest fragmentation affects winter flock formation of an insectivorous guild. Ardea 88:235241.
GOODALE E. & KOTAGAMA S. W. 2005. Testing the roles of species in mixed-species bird flocks in a Sri Lankan rain forest. Journal of Tropical Ecology 21:669676.
GOTELLI N. J. & ELLISON A. M. 2004. A Primer of Ecological Statistics. Sinauer Associates, Inc. Publishers, Sunderland. 479 pp.
GRAVES G. R. & GOTELLI N. J. 1993. Assembly of avian mixed-species flocks in Amazonia. Proceedings of the National Academy of Sciences, USA 90:13881391.
GRIMMETT R., INSKIPP C. & INSKIPP T. 1998. Birds of the Indian Subcontinent. Oxford University Press, Delhi. 784 pp.
HAILA Y. 2002. A conceptual genealogy of fragmentation research: from island biogeography to landscape ecology. Ecological Applications 12:321334.
HART P. J. & FREED L. A. 2003. Structure and dynamics of mixed-species flocks in a Hawaiian rainforest. The Auk 120:114.
HUTTO R. 1994. The composition and social organization of mixed-species flocks in a tropical deciduous forest in western Mexico. The Condor 96:105118.
JULLIEN M. & CLOBERT J. 2000. The survival value of flocking in neotropical birds: reality or fiction? Ecology 81:34163430
JULLIEN M. & THIOLLAY J.-M. 1998. Multi-species territoriality and dynamics of neotropical understory bird flocks. Journal of Animal Ecology 67:227252.
KOTAGAMA S. W. & GOODALE E. 2004. The composition and spatial organisation of mixed-species flocks in a Sri Lankan rainforest. Forktail 20:6370.
KREBS C. J. 1989. Ecological methodology. Harper Collins Publishers, New York. 654 pp.
LATTA S. C. & WUNDERLE J. M. 1996. The composition and foraging ecology of mixed-species flocks in pine forests of Hispaniola. The Condor 98:595607.
LEE T. M., SOH M. C. K., SODHI N., KOH L. P. & LIM S. L. H. 2005. Effects of habitat disturbance on mixed species bird flocks in a tropical sub-montane rainforest. Biological Conservation 122;193204.
LOVEJOY T. E., BIERREGAARD R. O., RYLANDS A. B., MALCOLM J. B., QUINTELA C., HARPER L. H., BROWN K. S., POWELL A. H., POWELL G. V. N., SCHUBART H. O. R. & HAYS M. B. 1986. Edge and other effects of isolation on Amazon forest fragments. Pp. 257285 in Soulé M. A. (ed.) Conservation biology. The science of scarcity and diversity. Sinauer Associates, Sunderland.
MALDONADO-COELHO M. & MARINI M. A. 2000. Effects of forest fragment size and successional stage on mixed-species bird flocks in southeastern Brazil. Condor 102:585594.
MALDONADO-COELHO M. & MARINI M. A. 2004. Mixed-species bird flocks from Brazilian Atlantic forest: the effects of forest fragmentation and seasonality on their size, richness and stability. Biological Conservation 116:1926.
MENON V. 2003. A field guide to Indian mammals. Dorling Kindersley, New Delhi. 200 pp.
MCCLURE H. E. 1967. The composition of mixed species flocks in lowland and sub-montane forests of Malaya. Wilson Bulletin 79:131154.
MORSE D. H. 1977. Feeding behavior and predator avoidance in heterospecific groups. Bioscience 27:332339.
MOYNIHAN M. 1962. The organization and probable evolution of some mixed species flocks of neotropic birds. Smithsonian Miscellaneous Collections 143:1140.
MUNN C. A. & TERBORGH J. W. 1979. Multi-species territoriality in neotropical foraging flocks. Condor 81:338347.
MYERS N., MITTERMEIER R. A., MITTERMEIER C. G., DA FONSECA G. A. B. & KENT J. 2000. Biodiversity hotspots for conservation priorities. Nature 403:853858.
NAIR S. C. 1991. The southern Western Ghats: a biodiversity conservation plan. INTACH, New Delhi. 92 pp.
PASCAL J. P. 1988. Wet evergreen forest of the Western Ghats of India: ecology, structure, floristic composition, and succession. Institut Français de Pondichéry, Pondicherry. 345 pp.
POWELL G. V. N. 1979. Structure and dynamics of interspecific flocks in a neotropical mid-elevation rainforest. Auk 96:375390.
POWELL G. V. N. 1989. On the possible contribution of mixed species flocks to species richness in neotropical avifaunas. Behavioral Ecology and Sociobiology 24:387393.
RAMAN T. R. S. 2001. Community ecology and conservation of tropical rainforest birds in the southern Western Ghats, India. PhD thesis, Indian Institute of Science, Bangalore.
RAMAN T. R. S. 2003. Assessment of census techniques for inter-specific comparisons of tropical rainforest bird densities. Ibis 145:921.
RAMAN T. R. S., RAWAT G. S. & JOHNSINGH A. J. T. 1998. Recovery of tropical rainforest avifauna in relation to vegetation succession following shifting cultivation in Mizoram, north-east India. Journal of Applied Ecology 35:214231.
SRIDHAR H. 2005. Patterns in mixed-species flocking of birds in rainforest fragments of the southern Western Ghats. MSc thesis, Wildlife Institute of India, Dehradun.
STATTERSFIELD A. J., CROSBY M. J., LONG A. J. & WEGE D. C. 1998. Endemic bird areas of the world: priorities for biodiversity conservation. Birdlife International Conservation Series No. 7, Cambridge. 848 pp.
STOTZ D. F. 1993. Geographic variation in species composition of mixed species flocks in lowland humid forests in Brazil. Papéis Avulsos Zoologia 38:6175.
STOUFFER P. C. & BIERREGAARD R. O. 1995. Use of Amazonian forest fragments by understory insectivorous birds. Ecology 76:24292445.
TELLERÍA J. L., VIRGÓS E., CARBONELL R., PÉREZ-TRIS J. & SANTOS T. 2001. Behavioural responses to changing landscapes: flock structure and anti-predator strategies of tits wintering in fragmented forests. Oikos 95:253264.
TERBORGH J. W. 1990. Mixed flocks and polyspecific associations: costs and benefits of mixed groups to birds and monkeys. American Journal of Primatology 21:87100.
TERBORGH J., LOPEZ L., NUÑEZ P., RAO M., SHAHABUDDIN G., ORIHUELA G., RIVEROS M., ASCANIO R., ADLER G. H., LAMBERT T. D. & BALBAS L. 2001. Ecological meltdown in predator-free forest fragments. Science 294:19231926.
THIOLLAY J.-M. 1993. Response of a raptor community to shrinking area and degradation of tropical rain forest in the South Western Ghats (India). Ecography 16:97110.
THIOLLAY J.-M. 1997. Disturbance, selective logging and bird diversity: a Neotropical forest study. Biodiversity and Conservation 6:11551173.
THIOLLAY J.-M. 1999a. Responses of an avian community to rainforest degradation. Biodiversity and Conservation 8:513534.
THIOLLAY J.-M. 1999b. Frequency of mixed species flocking in tropical forest birds and correlates of predation risk: an intertropical comparison. Journal of Avian Biology 30:282294.
TURNER I. M. 1996. Species loss in fragments of tropical rainforest: a review of the evidence. Journal of Applied Ecology 33:200209.
VAN HOUTAN K. S., PIMM S. L., BIERREGAARD R. O., LOVEJOY T. E. & STOUFFER P. C. 2006. Local extinctions in flocking birds in Amazonian forest fragments. Evolutionary Ecology Research 8:129148.
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Journal of Tropical Ecology
  • ISSN: 0266-4674
  • EISSN: 1469-7831
  • URL: /core/journals/journal-of-tropical-ecology
Please enter your name
Please enter a valid email address
Who would you like to send this to? *
×

Keywords:

Metrics

Full text views

Total number of HTML views: 1
Total number of PDF views: 16 *
Loading metrics...

Abstract views

Total abstract views: 210 *
Loading metrics...

* Views captured on Cambridge Core between September 2016 - 21st January 2018. This data will be updated every 24 hours.