Leach's Storm-Petrel

Oceanodroma leucorhoa

  • Version: 2.0 — Published July 31, 2019
  • Ingrid L. Pollet, Alexander L. Bond, April Hedd, Charles E. Huntington, Ronald G. Butler, and Robert Mauck

Free Introduction Article Access

The Introduction Article is just the first of 11 articles in each species account that provide life history information for the species. The remaining articles provide detailed information regarding distribution, migration, habitat, diet, sounds, behavior, breeding, current population status and conservation. Each species account also includes a multimedia section that displays the latest photos, audio selections and videos from Macaulay Library’s extensive galleries. Written and continually updated by acknowledged experts on each species, Birds of North America accounts include a comprehensive bibliography of published research on the species.

A subscription is needed to access the remaining account articles and multimedia content.

Subscribe Now

Already a subscriber? Sign In
Figure 1. Distribution of the Leach's Storm-Petrel in North America.
Leach’s Storm-Petrel (4 August).

In flight, Leach's Storm-Petrels are generally dark brown and show a forked tail, white uppertail coverts and transverse pale bars across the upperwing coverts. Typical for northern breeding individuals, including all or virtually all of those in the Atlantic Ocean, the uppertail coverts ("rump") are white. This individual is in Definitive Basic Plumage by, among other things, the "molt cline" in the primaries, browner inner feathers becoming darker distally, evidence of a previous prebasic molt.

© Alix d'Entremont , Nova Scotia , Canada , 4 August 2017
Leach's Storm-Petrel (25 July).

White rump usually, not always, divided by highly variable median "smudge," which becomes more prominent southward in Pacific, with completely dark-rumped populations at southeast end of Pacific range.

© Brian Sullivan , California , United States , 25 July 2009

This species account is dedicated in honor of Chuck Huntington, director of the Bowdoin Scientific Station on Kent Island (1953–1989), and Bill Ellison, a member of the Cornell Lab of Ornithology's Administrative Board.

Leach's Storm-Petrel, also known as Leach's Petrel or Mother Cary's Chicken, is the most widespread procellariiform breeding in the Northern Hemisphere. More than 6 million pairs nest in burrows or crevices on Atlantic islands from Norway to Massachusetts and on Pacific islands from Baja California to Hokkaido, Japan. Outside the long nesting season, these seabirds disperse widely in the Atlantic and Pacific oceans, well away from land and mainly in the tropics. Millions more nonbreeding individuals, mostly immatures, remain at sea year-round, although many of them visit colonies during the nesting season, often covering vast distances. Small and dark and not usually gregarious or attracted to ships, this species is inconspicuous at sea. Much work remains to determine the nonbreeding distributions of these populations.

Populations breeding on Guadalupe Island off Baja California are now considered separate species; the summer-breeding Townsend’s Storm-Petrel (O. socorroensis) and winter-breeding Ainley’s Storm-Petrel (O. cheimomnestes). The smaller, dark-rumped Swinhoe's Storm-Petrel (Oceanodroma monorhis), nesting off Japan, Korea, China, and Russia, is so similar that it has been considered a race of Leach's Storm-Petrel; the two are appropriately considered a superspecies.

Like all storm-petrels (as far as it is known), this species feeds on zooplankton and nekton at the surface of the sea, pecking at individual organisms while hovering, resting briefly on the surface, or, rarely, pattering with wings partly spread. Nesting in burrows dug on wooded or treeless islands or in crevices among rocks, individuals return faithfully each year to their colony. While individuals fly to and from their subterranean nests over their colonies at night, they utter a loud Chatter Call; in the nest they produce a Purring Call, often as a duet, for many minutes at a time. Like all procellariiforms, this species is long-lived and lays only one egg per year. Both sexes incubate and feed the young, which develops slowly and becomes very fat before slimming down to flying mass in the fall.

Recommended Citation

Pollet, I. L., A. L. Bond, A. Hedd, C. E. Huntington, R. G. Butler, and R. Mauck (2019). Leach's Storm-Petrel (Oceanodroma leucorhoa), version 2.0. In The Birds of North America (P. G. Rodewald, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.lcspet.02