Population estimates and distribution changes of landbirds on Silhouette Island, Seychelles

Cresswell, W., Irwin, M., Mee, A., Mellanby, R., McKean, M. & Milne, L. 1997. Population estimates and distribution changes of landbirds on Silhouette Island, Seychelles. Ostrich 68 (2–4): 50–57. The density of landbird species within different habitats, and presence within 4 ha squares, on Silhouette Island were recorded in August 1996, repeating a previous survey (January 1979). Densities of the four most common species were calculated from point counts: Seychelles Sunbirds occurred at 2–5 birds/ha, Seychelles Bulbuls 0.5–4 birds/ha, Indian Mynahs 0.2–2 birds/ha and Seychelles Blue Pigeons 0.3 birds/ha depending on habitat. Population estimates were: Seychelles Sunbirds 5600, Seychelles Bulbuls 4000, Indian Mynahs 1100, Seychelles Blue Pigeons 600, and Seychelles Kestrel, approximately 15 pairs. The distributions of non-endemic Indian Mynahs, Barred Ground Doves and Madagascar Fodies were smaller in 1996 compared to 1979, while those of endemic Seychelles Bulbuls and Sunbirds were larger. Mynahs were mo...