Hydrobates tethys
The Wedge-rumped Storm Petrel (Hydrobates tethys) is a diminutive and enigmatic pelagic seabird, epitomizing the life of the open ocean. Averaging 14-16 cm in length with a wingspan of 33-36 cm and weighing a mere 20-30 grams, it is characterized by its entirely sooty-black plumage, sharply contrasted by a striking white, wedge-shaped rump patch that extends up the flanks. This prominent field mark, along with its buoyant, erratic flight often described as 'walking on water' while foraging, d...
Exclusively pelagic, inhabiting tropical and subtropical oceanic waters. Breeds nocturnally on arid offshore islands, nesting in rock crevices or burrows.
Feeds primarily on small crustaceans, fish larvae, small cephalopods, and other planktonic organisms, often scavenging on oil slicks and associated detritus. Forages by surface-seizing and dipping.
Primarily nocturnal at its breeding colonies to avoid predation, while diurnal and highly active at sea. Its foraging strategy involves 'surface-patting' - fluttering its wings and appearing to walk on the water's surface, dipping its bill to pick small prey. Nesting is colonial, often in dense a...
The Wedge-rumped Storm Petrel's breeding range is highly restricted to a few offshore islands in the eastern tropical Pacific Ocean. The nominate subspecies, *H. t. tethys*, breeds predominantly on the Galápagos Islands, notably on Genovesa, Floreana, and Española, with smaller populations on oth...
Near Threatened
- The Wedge-rumped Storm Petrel is one of the few seabirds that truly appears to 'walk on water' as it forages, fluttering its wings just above the surface. - Its scientific name, *tethys*, is derived from the Greek mythological sea nymph Tethys, symbolizing its deep connection to the ocean. - Th...