Sabine's gull 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. On the basis of this the two species were often thought to be each other's closest relatives, a hypothesis ruled out by a number of behaviour and ecological differences. Mitochondrial DNA studies confirmed that they are not closely related, and the closest relative of the Sabine's gull is now thought to be the ivory gull, another Arctic
Fork-tailed storm petrel Fork-tailed storm petrel The fork-tailed storm petrel ("Oceanodroma furcata" or "Hydrobates furcatus") is a small seabird of the storm petrel family Hydrobatidae. It is the second most abundant and widespread storm petrel (after the Leach's storm petrel) and is the only bird in its family that is bluish-grey in colour. The fork-tailed storm petrel is pelagic, spending up to 8 months in the northern Pacific ocean. They only return to land to breed, where they nest in a colony. Their nest can be found in a rock crevice or small burrow where a single egg is laid. Their breeding range