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 flycatcher Fork-tailed flycatcher The fork-tailed flycatcher ("Tyrannus savana") is a passerine bird of the tyrant flycatcher family, and is the member of a genus typically referred to as kingbirds. This bird occurs in a wide variety of habitats including pastures, riparian forests, and open residential areas with scattered trees. Its breeding range is from central Mexico to central Argentina. In most of this range it is usually found year-round, but in the southern parts of its range it retreats northward for the winter. This species is also known to wander widely. It occurs almost annually in the eastern United States seaboard