Ashy Storm-Petrel (Oceanodroma homochroa)

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The Ashy Storm-Petrel (Oceanodroma homochroa) is a relatively rare little bird that can be found in colonies on small islands off the coast of California and Mexico. The bird is part of the storm-petrel family Hydrobatidae and it is currently an endangered species. The Ashy Storm-Petrel is also one of 6 species of storm-petrel which feed off the California Current system. Both sexes are similar in appearance and they are fairly easily confused with other storm-petrel species.

The most notable difference between Ashy Storm-Petrels and other storm-petrels is that the Ashy Storm-Petrel does not have a white rump. They are also smaller in size with shallower wingbeats than Black Storm-Petrels, while the Least Storm-Petrel has even shallower wingbeats than the Ashy, and a wedge-shaped tail. The Ashy Storm-Petrel is medium-sized with a length of 7 inches and a wingspan of 16 inches. Its body coloring is a sooty brown – hence the name – and it has a dark rump and forked tail. The underwings are somewhat paler than the rest of the bird and the bill is dark in color with a tube on top. The Ashy Storm-Petrel has a somewhat ‘fluttering’ style of flight and its upstroke is not as high as certain other members of the storm-petrel family. It feeds on a variety of sea creatures such as cephalopods, fish, krill and other organisms which might be found near the sea’s surface.

Ashy Storm-Petrels are nocturnal and they have a long breeding cycle. They make their nests in rock burrows on offshore islands and it takes about five months from the time the egg is laid to fledging. Both male and female tend to show fidelity, mating with the same mate for many years. They usually only change their mate if they change their nesting site. Records show that the Ashy Storm-Petrel is a relatively long-lived bird with current records allowing for a lifespan of approximately 30 years. Currently most Ashy Storm-Petrel breeding colonies fall within protected areas and wildlife refuges whose legislative protection has helped to ensure the survival of this beautiful little endangered bird.