[ste]

Hello All,
After seeing the Sooty Tern at Cemlyn Bay I Thought I would look through my bird books to see what I could find out about this beautiful tern. I read in "birds of the world " by David Alderton that amazingly sooty terns can not swim but will spend 3 months out in the oceans and will sleep on the wing. I found this very strange for an ocean going seabird. My Question is why can't sooty terns swim, is it their body shape or is it that their feathers are not suitable. I did see the sooty tern at cemlyn bay land on the water whilst being chased by the sandwich terns but it seemed to struggle, flapping its wings as if it was taking a bath and was airbourne a couple of seconds later.
Ste
ps When I say swim I mean float on the water as a gull would do.

[Rasmus Boegh]

Not the Worlds best photo, but it still show enough:

http://www.marn.gob.sv/patrimonio/or...%20fuscata.jpg

It's certainly a rare occurrence, though.

[ed keeble]

Originally Posted by Rasmus Boegh

Not the Worlds best photo, but it still show enough:

http://www.marn.gob.sv/patrimonio/or...%20fuscata.jpg

It's certainly a rare occurrence, though.

It may be an adaptation to avoid predation- Sooties tend to hang out where there is a lot of shark activity and Tiger Sharks (for example) certainly take birds off the surface.

[Hanno]

According to HBW, Sooty Terns do not have water-proof plumage. It therefore remains a mistery waht they do for the first 5 years of their lives when they do not make a single landfall. HBW further goes on to state that Terns in general rarely swim, even though many species juveniles swim very well.

[James Eaton]

I wonder if it has anything to do with exhaustion as to when Terns decide to land on the water. Though I have on many ocassions seen Common Terns sitting on water (and have photographed them doing so in South Africa).
I remember once observing up to 50 Arctic Terns sitting on the ocean from a pelagic off California, we watched them for several minutes until the boat got quite close to them, and they all took off and headed south.

[ste]

Thanks for those interesting replies.

Sooty terns are perfectly formed for the skies with their long powerful wings and slender bodies. They scoop their prey from the waters surface so they have no need to enter the sea but its certainly an amazing feat to stay on the wing for so long.
Ste