Observations on Great and Lesser Frigatebirds (Fregata minor and F. ariel).

The Frigate bird is an iconic species in Seychelles - soaring on the breeze a large dark bird with its characteristic arched wing profile silhouetted against the bright blue sky - it has been adopted as a symbol by 3 islands in the central archipelago. Both species can be seen quite regularly in the central archipelago, though neither breed here, their nearest large breeding colonies being situated on Aldabra.

Aride island hosts the largest roost in the central archipelago with a seasonal peak of some 4,500 birds. Skerrett et al (2001)[1] states that small roosting populations also occur on Cousin and Bird Island. I lived on Cousin (1990-91) and clearly recall Frigatebirds roosting in a single casuarina tree, ignoring all others, north of “Anse Fregate”. That tree latterly fell however and I do not know whether the small roosting population on Cousin persists today. What I do know however is that Denis harbours a regular if small roost of some 40- 50 birds. Both species are represented though as is normal throughout the central archipelago the great out number the lesser.

On the Saturday morning of my last visit to the island I observed 6 frigatebirds stunting and swooping at not too high an altitude over the runway so I took some photos in the hope that the results would be good enough to differentiate between the species for the blog.

The photos are not the best – standing looking almost directly upwards, trying to zoom on and photograph rapidly moving birds not being one of my strong points! – but they are sufficient however to discern identifying characteristics.

The lesser frigatebird adult has the abbreviated white chest and inner wing patch, whilst the adult male great frigatebird is entirely black save for its red throat patch (barely visible in the sidebar photo).

Interestingly I was also able to photo two immature great frigate birds one white-headed and one buff-headed. Skerrett et al (2001) state that the white-headed birds are from the Aldabra colony whilst the buff-headed sub-adults originate form breeding colonies even farther afield! Click on the images below to enlarge.

[1] Skerrett et al (2001). Birds of Seychelles. Helm Field Guides, London.