In all the years humans have been photographing birds in flight, no one has ever caught one with an obvious baby bump, or at least not in a way that has been brought to wider attention. That’s until the photograph above was taken.
According to the Bulletin of the British Ornithologists’ Club, the bird is a Mascarene petrel (Pseudobulweria aterrima), a critically endangered species found near the Indian Ocean island of Réunion. The petrel’s eggs are large relative to the size of the bird, creating the distinctive bump seen in the photograph. They build up fat reserves during long periods at sea to nurture their eggs.
Most familiar land birds have feathers that disguise their shape while seabird feathers cling to the body to help prevent waterlogging. However, since seabirds nest in burrows and often come to shore a night, their maternal status can be equally hard to spot. The petrel usually lay their eggs in late October or November, so the fact that this photo was taken on December 22 last year indicates something may have disrupted the breeding cycle. Only 100 adult pairs are thought to survive at four colonies threatened by rats, cats and streetlight-induced collisions.
The photographer, Hadoram Shirhai said, “Against the background of a pinkish-orange sunset, with Reunion Island in the distance, I spotted a petrel through my camera’s viewfinder. Almost immediately I saw the outline of an egg, a huge bump at its belly. I called out to the other expedition members – ‘she has an egg, she has an egg...’ She flew close to the boat which gave me a unique chance to photograph her just before the sun set. It was a magical moment.”
Hadoram Shirihai/Tubenoses project. Shirihai's first photograph of the Petrel.
Shirhai estimates the bird laid its egg less than an hour later. The little-studied petrel has never been photographed at sea before, with this shot captured because Shirhai was a member of a team that was dumping blocks of frozen fish and fish oil to attract seabirds.
The photograph has been publicized by Birdlife International, who are working to protect the petrel through conservation efforts on Reunion.
H/T Science