I did not know that

 

The BBC has an interesting article (if you're interested in natural and human history) about Bird Island in the Seychelles, which has been transformed into a nature reserve and bird sanctuary.  Its focus is the sooty tern, a bird of which I'd never heard before.

Sooty terns are remarkable birds. They have no oil in their feathers and are, therefore, unable to float. Most sooty terns only land when nesting and rearing their young. At Bird Island, that's from April or May to October.

"Between seasons, they spend the whole time on the wing: they do not return to land to roost or to rest," said Rachel Bristol, an expert in sooty terns with extensive experience of Bird Island and its breeding colonies; she is currently collaborating with the Max Planck Institute of Animal Behaviour to track around 250 sooty terns. "They obviously do sleep, but they probably sleep for short bursts frequently while flying, and may be able to shut down the two halves of the brain separately so that they are always aware of what is around them." Just as incredibly, she said, "they can clearly spend years airborne: when they fledge, they possibly do not return to land until they reach breeding age, which is around five years old."

The sooty terns on Bird nest ... at a density of seven nests per square metre, spread across the 13-hectare breeding colony. Bird Island is now one of the world's largest bird breeding colonies – and, said Bristol, one of the most important and best-managed such colonies anywhere in the Seychelles archipelago.

With so many sooty terns on an island that covers less than 1 sq km of land, it's easy to imagine that there would be little room for anything else. But the island's portfolio of resident and migrant avifauna is rich and varied and includes terns and tropicbirds, plovers and ruddy turnstones, shearwaters and even a resident population of the handsome Seychelles blue pigeon. Even the island's shape resembles a bird: if you look at a satellite image of Bird Island, it resembles in outline a coquettish dove adrift in the Indian Ocean. And so rich is the birdlife here that Bird took on a starring role in two episodes of Sir David Attenborough's classic The Life of Birds, broadcast in 1998 and 1999.

There's more at the link.

I visited the Seychelles way back when, but I'd never heard of Bird Island before.  (At the time of my visit it hadn't yet been fully cleared of invasive species or rehabilitated into a bird sanctuary, so perhaps that's not surprising.)  I'd love to visit it and experience the peace and quiet for myself (well, "quiet" is perhaps relative, with hundreds of thousands of birds all over the place!).  If you're ever in that part of the world, it might be worth a detour.

Peter