Ivory Gull
Ivory Gull is the most northerly bird on the planet. It breeds in the far north in areas adjacent to ice fields and has been recorded closer to the North Pole than any other bird species. It doesn't venture far in winter, usually wintering on the sea-ice edge in the winter twilight zone. It has a few adaptations for living in extreme cold conditions. First it has very short legs (tarsometatarsi) as they are the parts it loses most heat through. The second adaptation is rarely visible but it is in this photo. It has reduced webbing between its toes compared with other gulls, which reduces the area through which it can lose body heat. It still needs webbed feet to swim, but it avoids swimming when the water is sub zero. And this is what normal webbing looks like on the feet of a (Glaucous) Gull for comparison: www.flickr.com/photos/timmelling/53075167254/in/photolist
Ivory Gull
Ivory Gull is the most northerly bird on the planet. It breeds in the far north in areas adjacent to ice fields and has been recorded closer to the North Pole than any other bird species. It doesn't venture far in winter, usually wintering on the sea-ice edge in the winter twilight zone. It has a few adaptations for living in extreme cold conditions. First it has very short legs (tarsometatarsi) as they are the parts it loses most heat through. The second adaptation is rarely visible but it is in this photo. It has reduced webbing between its toes compared with other gulls, which reduces the area through which it can lose body heat. It still needs webbed feet to swim, but it avoids swimming when the water is sub zero. And this is what normal webbing looks like on the feet of a (Glaucous) Gull for comparison: www.flickr.com/photos/timmelling/53075167254/in/photolist