Black Storm-Petrel Hydrobates melania Scientific name definitions

The Black Storm-Petrel inhabits tropical, subtropical, and warm-temperate waters of the extreme eastern North Pacific Ocean, where it nests in xeric habitat on islands. Its breeding range overlaps broadly with several other all-dark Oceanodroma storm-petrels, often cohabiting the same islands and even (sometimes sequentially) the same nesting crevices. Nesting habitat is divided on the basis of a nesting cavity-size to body-size relationship. As is true of most all-dark forms, the Black Storm-Petrel does not excavate its own nesting cavity, unlike many other storm-petrel species. Like almost all storm-petrels, the Black Storm-Petrel is active at colonies only at night, a defense against avian predators. Breeding populations are limited by availability of nesting habitat and have been affected immensely by the introduction of feral and predatory mammals to islands.

Similar to other seabirds that nest in the Gulf of California, the Black Storm-Petrel exhibits an unusual bifurcation in its overwintering range. The species vacates the Gulf of California and southern Pacific Baja California coast, with some portion of the population moving north to waters off southern and central California and another, larger portion, moving south to waters off Central America and northern South America. This range bifurcation may be an adaptive strategy to avoid entrapment by hurricanes in the Gulf of California and along the adjacent Mexican coast.

The Black Storm-Petrel has been little studied on its nesting grounds, owing to the difficult habitat it occupies on breeding islands (rocky talus with dense growth of cactus). What is known mostly confirms a basic storm-petrel life-history strategy: burrow-nesting, nocturnal nest visitation, 1-egg clutch, slow chick growth, etc. (cf. 1 Everett, W. T. (1991). Breeding biology of the Black Storm-Petrel at Islas Los Coronados, Baja California, Mexico. Unpubl. Master's Thesis, Univ. of San Diego, San Diego, CA. Close , 2 Ainley, D. 1995. Ashy Storm-Petrel (Oceanodroma homochroa). In The Birds of North America, No. 185 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, and The American Ornithologists' Union, Washington D.C. Close , 3 Huntington, C. E., R. G. Butler, and R. A. Mauck. 1996. Leach's Storm-Petrel (Oceanodroma leucorhoa). In The Birds of North America, No. 233 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' Union, Washington D.C. Close ). What is remarkable is the concentration of so many storm-petrel species among the islands of Baja California (Mexico) and southern California (United States), with diversification seemingly related to body size and use of marine habitat. Upon extinction of the Guadalupe Storm-Petrel (H. macrodactyla) in the 20^th century, the Black Storm-Petrel is now the largest and is the most inshore of the group.