Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-26T17:32:48.552Z Has data issue: false hasContentIssue false
  • English
  • Français

Studies of birds in a semi-arid area of Kenya. III The use of ‘Timed Species-counts’ for studying regional avifaunas

Published online by Cambridge University Press:  10 July 2009

Derek Pomeroy  and
Beatrice Tengecho
Derek Pomeroy
Affiliation:
Department of Zoology, Kenyatta University, Nairobi, Kenya
Beatrice Tengecho
Affiliation:
Department of Zoology, Kenyatta University, Nairobi, Kenya
Get access Rights & Permissions [Opens in a new window]

Abstract

‘Times Species-counts’ are a simple method of comparing the avifaunas of extensive areas by sampling representative habitats. The method has been evaluated in south central Kenya but could be applied to most terrestrial regions of tropical Africa. The essential feature is that the observers move anywhere within a sample site of about 1 km2, recording all of the species seen in a fixed time, e.g. 1 h.

Counts are made in all seasons and at various times of day. Reasonable estimates of the total number of species in an area can be derived from a series of 15 counts, but such estimates tend to be low in non-forested habitats because ‘wanderers’ (non-resident species) continue to be recorded almost indefinitely. Open sites have far fewer species than well-wooded areas. The numbers of resident species in non-forested terrestrial habitats is related both to the amount of woody vegetation and to a measure of plant growth. However, total species numbers seem to depend solely on the amount of woody vegetation. Road counts, from a vehicle, were compared to those made on foot. They are less satisfactory, especially for cryptic species.

Keywords

bird countshabitat comparisonsKenyasemi-aridtimed species-counts
Type
Research Article
Information
Journal of Tropical Ecology , Volume 2 , Issue 3 , August 1986 , pp. 231 - 247
Copyright
Copyright © Cambridge University Press 1986

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

Bailey, H. P. 1979. Semi-arid climates: their definition and distribution. Pp. 73–97 in Hall, E. A., Connell, C H. & Lawton, H. W. (eds) Agriculture in semi-arid environments. Springer-Verlag, Berlin.CrossRefGoogle Scholar
Britton, P. L. (ed.). 1980. Birds of East Africa. East African Natural History Society, Nairobi.Google Scholar
Dawson, D. G. 1981. The usefulness of absolute (‘census’) and relative (‘sampling’ or ‘index’) measures of abundance. Pp. 554–558 in Ralph & Scott, q.v.Google Scholar
Dawson, D. G. 1985. A reivew of methods for estimating bird numbers. Pp. 27–33 in Taylor, et al. , q.v.Google Scholar
Diamond, J. M. 1980. Why are many tropical bird species distributed patchily with respect to available habitat? Pp. 968–973 in Nöhring, R. (ed.). Acta XVII Congressus Intemationalis Ornitholgici. Verlag der Deutscher Ornithologen-Gesellschaft, Berlin.Google Scholar
Fuller, R. J. & Langslow, D. R. 1984. Estimating numbers of birds by point counts: how long should counts last? Bird Study 31:195–202.CrossRefGoogle Scholar
Gichuki, N. N. – Pomeroy, D. E. 1983. The populations, diet, and pest status of two doves of the genus Streptopelia in eastern Machakos District. Kenya Journal of Science & Technology (B) 4:97–110.Google Scholar
Granholm, S. L. 1981. Bias in density estimates due to movements of birds. Pp. 243–248 in Ralph, & Scott, , q.v.Google Scholar
Kenworthy, J. M. 1966. Temperature conditions in the tropical highland climates of East Africa. East Africa Geographical Review 4:4–6.Google Scholar
Kingdon, J. 1974. East African Mammals: An Atlas of Evolution in Africa. Vol 1. Academic Press, New York.Google Scholar
Lack, P. C. 1980. The feeding stations of land-birds in Tsavo East National Park. Unpublished D. Phil. thesis, Oxford University, Oxford.Google Scholar
Lack, P. C., Leuthold, W. & Smeenk, C. 1980. A check-list of the birds of Tsavo National Park, Kenya. Journal of the East African Natural History Society and National Museum 170:1–25.Google Scholar
Lewis, A. D. & Pomeroy, D. E. In press. A Bird Atlas for Kenya. Balkema, Rotterdam.Google Scholar
Norton-Griffiths, M. 1977. Aspects of climate of Kajiado District. UNDP/FAO Kenya Wildlife Management Project. Nairobi, Kenya.Google Scholar
Pomeroy, D. E. & Lewis, A. D. In press. Bird species-richness in Africa: some comparisons. Biological Conservation.Google Scholar
Pomeroy, D. E. & Muringo, C. 1984. Studies of birds in a semi-arid region of Kenya. L The use of transects to assess the effects of bush-clearance on bird populations. Proceedings of the Fifth Pan-African Ornithological Congress: 179–199.Google Scholar
Pomeroy, D. E. & Tengecho, B. 1982. Studies of birds in a semi-arid region of Kenya. II. Bird parties in two woodland areas. Scopus 6:25–32.Google Scholar
Pomeroy, D. E. & Tengecho, B. In press. A method of analyzing bird distributions. African Journal of Ecology.Google Scholar
Pratt, D. J. & Gwynne, M. D. (eds). 1977. Rangeland management and ecology in East Africa. Hodder & Stoughton, London.Google Scholar
Ralph, C. J. & Scott, J. M. (eds). 1981. Estimating numbers of terrestrial birds. Studies in Avian Biology No. 6. Cooper Ornithological Society, New York.Google Scholar
Reichholf, J. 1980. Komponenten des Artenreichtums der ostafricanischen Avifauna. Verhandlungen der Ornithologischen Gesellschaft in Bayern 23:371–385.Google Scholar
Southwood, T. R. E. 1978. Ecological methods. (2nd edition). Chapman & Hall, London.Google Scholar
Taylor, K., Fuller, R. J. & Lack, P. C. 1985. Bird census and atlas studies. British Trust for Ornithology, Tring.Google Scholar
Williams, J. G. 1981. A Field Guide to the National Parks of East Africa. (2nd edition). Collins, London.Google Scholar
Zimmerman, D. A. 1972. The avifauna of the Kakamega Forest, western Kenya, including a bird population study. Bulletin of the American Museum of Natural History 149:257–339.Google Scholar