Wedge-tailed shearwater have long, wedge-shaped tails—as their name appropriately suggests—and broad wings that make them masterful gliders, effortlessly soaring over the open ocean. These birds come in two distinct color phases: light grey and dark grey. This variation isn’t linked to age, sex, or breeding status, and is a unique visual characteristic among the species.
Their haunting wail has earned them the Hawaiian name Ua’u Kani, which translates to “calling or moaning petrel.” It’s largely thought these wails play a role in their communication and social interactions.
An estimated 270,000 breeding pairs call the Hawaiian islands home and, as a highly abundant bird, there are likely many more across their entire range in the Pacific Ocean.
The wedge-tailed shearwater is a pelagic bird, spending most of its time flying across the ocean. They only come to land to breed, forming large colonies on remote islands with little to no vegetation. Low, flat islands, sand spits, and sandy dunes are their preferred nesting grounds. Wedge-tailed shearwaters dig burrows for their nests—unlike some seabirds that nest on cliff faces—which are excavated in firm soil with shallow roots. This offers protection from predators and Mother Nature.
Wedge-tailed shearwater are skilled hunters, primarily feeding on fish, squid, and crustaceans. They’ll always go for the easy meal on the surface, but don’t discount their ability to dive deep to grab their prey.
Historically, threats include predators (like feral cats, rats, and mongoose), coastal development and human disturbance, disorientation from artificial lighting, overfishing of their primary prey sources, and coastal pollution and marine debris.
Current conservation efforts to protect the wedge-tailed shearwater include:
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