Leach's Storm Petrel

The Leach's storm petrel, a diminutive seabird with the scientific moniker Hydrobates leucorhous, flutters over the ocean's expanse. Measuring 18–21 cm in length and boasting a wingspan of 43–48 cm, it is cloaked in predominantly dark plumage, save for a characteristically white rump—a trait it shares with many of its storm petrel kin. Yet, on the west coast of North America, one may encounter the rarer dark-rumped individuals.

Identification Tips

Distinguished by its forked tail and larger size, the Leach's storm petrel can be separated from its European and Wilson's counterparts in Europe with relative ease. However, in the Americas, particularly along the Pacific Coast, its identification becomes a meticulous task. Here, the dark-rumped variant mingles with other all-dark species, necessitating a keen eye for wingbeats and subtle color nuances to ensure accurate identification.

Habitat

Breeding in the secluded northern reaches of the Atlantic and Pacific, the Leach's storm petrel favors the shelter of rock crevices, shallow burrows, or even hollow logs close to the sea. Its breeding grounds are often remote and challenging to access.

Distribution

This species is a pelagic voyager, seldom seen from land except when storms drive it towards coastal headlands. It does not trail ships like its European relative, making sightings from land a rarity.

Behaviour

The Leach's storm petrel is a nocturnal creature at its breeding sites, a strategy to elude gulls and skuas. It shuns the land on moonlit nights, its presence betrayed only by its fluttering flight and water-pattering forays for food.

Song & Calls

The vocalizations of the Leach's storm petrel remain undocumented in this guide.

Breeding

A single white egg, sometimes adorned with a faint ring of purple spots, is laid within the petrel's concealed nest. The largest known colony is on Baccalieu Island, Canada, where nearly two million pairs were recorded in 2013.

Similar Species

In Europe, the European storm petrel and Wilson's storm petrel serve as points of comparison, while in the Americas, the band-rumped storm petrels and other all-dark species provide a challenge for differentiation.

Diet and Feeding

Leach's storm petrels feast on planktonic delicacies such as euphausiids, copepods, and amphipods, as well as myctophids that surface at night. They can forage up to 1000 km from their breeding colony, storing energy-rich lipids in a specialized sac for sustenance during incubation or chick-feeding.

Conservation status

The IUCN has classified the Leach's storm petrel as Vulnerable, indicating that this species faces a high risk of endangerment in the wild.