Temporal variation of colonial nesting waterbirds in eastern Uganda.

Abstract

The aim of this study was to investigate temporal variations in the populations of tree nesting colonial waterbirds in eastern Uganda. Counts of breeding pairs were made during a six year period: 2005 and 2008 to 2012. Eight waterbird species namely, Cattle Egret Bubulcus ibis, Pink-backed Pelican Pelicanus carbo, Sacred Ibis Threskiornis aethiopica, Yellow-billed Stork Mycteria ibis, African Spoonbill Platalea alba, Long-tailed Cormorant Phalacrocorax africanus, Little Egret Egretta garzetta and the Black-headed Heron Ardea melanocephala, were recorded breeding. There was a decline in the number of nesting sites and breeding pairs over time. The possible cause of this decline is the cutting down of nesting trees by man, particularly because most waterbirds chose to nest on the Mvule tree Milicia excelsa that is also a very good source of timber for the local communities. Except Pelicanus carbo, all the other waterbird species recorded breeding seem to have adapted to this habitat loss by nesting on other tree species like Cassia Cassia spectabilis and Mango Mangifera indica L. It is therefore desirable to find out how Pelicanus carbo is coping with this habitat loss.