Townsend's shearwater (''Puffinus auricularis'') is a rare

seabird Seabirds (also known as marine birds) are birds that are adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same enviro ...

of the

tropics The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also referr ...

from the family

Procellariidae The family Procellariidae is a group of seabirds that comprises the fulmarine petrels, the gadfly petrels, the diving petrels, the prions, and the shearwaters. This family is part of the bird order Procellariiformes (or tubenoses), which als ...

Taxonomy

Its relationships are unresolved. Its closest relatives are probably, but not certainly, the Hawaiian shearwater (''Puffinus newelli'') and possibly the Manx shearwater (''Puffinus puffinus'') (Austin, 1996; Austin ''et al.'', 2004). It formerly contained the former as a subspecies and was long considered a subspecies of the latter. The relationship of the Rapa shearwater, ''P. myrtae'' in regard to these species are also in need of research; this

taxon In biology, a taxon ( back-formation from '' taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular n ...

was until recently placed in '' P. assimilis'' (Austin ''et al.'', 2004), but now raised to full species status by the IOC and the NACC of the AOU.

Conservation

This species breeds around Cerro Evermann on

Isla Socorro Socorro Island ( es, Isla Socorro) is a small volcanic island in the Revillagigedo Islands, a Mexican possession lying off the country's western coast. The size is 16.5 by 11.5 km (10.25 by 7.15 miles), with an area of . It is the largest ...

in the

Revillagigedo Islands The Revillagigedo Islands ( es, Islas Revillagigedo, ) or Revillagigedo Archipelago are a group of four volcanic islands in the Pacific Ocean, known for their unique ecosystem. They lie approximately from Socorro Island south and southwest of C ...

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

, though formerly present on

Clarion Island Isla Clarión, formerly called Santa Rosa, is the second largest, westernmost and most remote of Mexico's Revillagigedo Islands. The island is located west of Socorro Island and over from the Mexican mainland. It has an area of and three pr ...

and San Benedicto. The main threat to this species comes from

feral cat A feral cat or a stray cat is an unowned domestic cat (''Felis catus'') that lives outdoors and avoids human contact: it does not allow itself to be handled or touched, and usually remains hidden from humans. Feral cats may breed over dozens ...

s introduced to Socorro in the early 1970s. These cats usually prey on shearwaters immediately after landing, where a lack of understory renders them exposed. Sheep and goats are also destroying breeding habitat. The Isla Clarión was eradicated in 1988, when habitat and nesting sites were destroyed by introduced pigs, sheep and rabbits, the final of which competed against the shearwaters for nesting burrows. Despite this, some breeding habitat remains to the north and north-west of Socorro's summit, where introduced animals have yet to ravage. The current mature population is estimated between 249 and 999 birds. Due to the presence of these threats, it has been classified as critically endangered. Further threat is posed by light pollution from a recently constructed airstrip and possible volcanic eruptions, the latter eradicated the San Benedicto population. Sheep and pigs have since been eradicated from Clarion, though rabbits have yet to follow. On Socorro, sheep eradication is currently in progress. The species is named for

Charles Haskins Townsend Charles Haskins Townsend (September 29, 1859 – January 28, 1944) was an American zoologist and naturalist who served as the director of the New York Aquarium, from 1902 to 1937. Early life The son of the Reverend Daniel W. Townsend and Elizabet ...

(1859-1944), eminent American ornithologist and ichthyologist.

References

*Austin, Jeremy J. (1996): Molecular Phylogenetics of ''Puffinus'' Shearwaters: Preliminary Evidence from Mitochondrial Cytochrome ''b'' Gene Sequences. ''Molecular Phylogenetics and Evolution'' 6(1): 77–88. (HTML abstract) *Austin, Jeremy J.; Bretagnolle, Vincent & Pasquet, Eric (2004): A global molecular phylogeny of the small ''Puffinus'' shearwaters and implications for systematics of the Little-Audubon's Shearwater complex. ''

Auk An auk or alcid is a bird of the family Alcidae in the order Charadriiformes. The alcid family includes the murres, guillemots, auklets, puffins, and murrelets. The word "auk" is derived from Icelandic ''álka'', from Old Norse ''alka'' (a ...

'' 121(3): 847–864. DOI: 10.1642/0004-8038(2004)121 847:AGMPOT.0.CO;
HTML abstract
Townsend's shearwater Natural history of the Revillagigedo Islands Endemic birds of Western Mexico Critically endangered animals Critically endangered biota of Mexico Critically endangered fauna of North America Townsend's shearwater Townsend's shearwater {{Procellariiformes-stub