Sabine's Gull
Xema sabini

f11 @ 1/1250s, ISO:800, Nikon D300 w 300mm

"Sabine's Gull," Wikipedia, the free encyclopedia. The Sabine's gull is usually treated as comprising a monotypic genus; it is only placed within the genus Larus when the genus is enlarged. The black bill and notched tail are almost unique within the gulls, as they are shared only with the swallow-tailed gull of the Galapagos.
Cambridge Bay, Nunavut, Canada