The San Clemente loggerhead shrike (''Lanius ludovicianus mearnsi'') or San Clemente Island loggerhead shrike is a

subspecies In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morpholog ...

of the loggerhead shrike that is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

San Clemente Island San Clemente Island (Tongva: ''Kinkipar''; Spanish: ''Isla de San Clemente'') is the southernmost of the Channel Islands of California. It is owned and operated by the United States Navy, and is a part of Los Angeles County. It is administer ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

, United States.

Description

The San Clemente loggerhead shrike is a

passerine A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped') which includes more than half of all bird species. Sometimes known as perching birds, passerines generally have an anisodactyl arrangement of their ...

bird of medium size. Around its eyes, it has black feathers, a color which is also found in the tail and on the wings. On its back, it has gray feathers. The underside of the bird is white. It also has patches of white on its wings and tail. The San Clemente loggerhead shrike has the darkest gray feathers compared to its other loggerhead shrike counterparts.

Genetics/Phylogeny

It has been known that the Santa Catalina loggerhead shrike population had clustered closely with the San Clemente loggerhead shrikes, so there has been historic gene flow between the two. Still, the San Clemente loggerhead shrike is now its own subspecies.

Behaviour

The San Clemente loggerhead shrike is also called a "butcher bird" since it can take animals similar to its own size such as mammals and reptiles. Loggerhead shrikes have "tomial teeth". These projections in their mandible jab at the spinal cord of their prey to paralyze them. Similar to other loggerhead shrikes, San Clemente loggerhead shrikes reach maturity after a year and live in monogamous pairs. The pair both care for the eggs and young. The clutch size is usually around five eggs.

Distribution and habitat

The San Clemente loggerhead shrike is native to San Clemente Island, a small island off the coast of California,

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

. The island is owned by the

United States Navy The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...

, and is a valuable asset to the Pacific fleet, allowing for ship-to-shore, air-to-ground, and ground-to-ground operational training. Shrikes typically occupy wooded canyons on the west side of the island, and sagebrush-dominant habitat on the eastern escarpment.

Conservation

Since the 1880s, the San Clemente loggerhead shrike's habitat has been threatened by domestic animals, primarily goats, imported to San Clemente Island. The predation of the shrikes by cats and rats also played a role. By the early 1900s, the bird's population had declined to about 20, but stabilized. The Navy began removing

introduced species An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived ther ...

in 1973. In 1977, the San Clemente loggerhead shrike was listed as endangered by the United States government, with an estimated population of 50. Between 1982 and 1999, the bird's population was measured between 14 and 33 birds, bottoming out in January 1998. The removal of feral goats and sheep was completed in 1993. In 1996, the Institute for Wildlife Studies conducted video research on the shrike for the Navy. In 1997, they were asked to come up with a strategy to raise the bird's numbers. A captive breeding program was launched in 1992 at a cost of $3 million per year, and new policies were instituted to help the shrike. For example, snipers must aim around bird nests when practicing. Thanks to the program, the bird's population reached 135 (captive and wild) specimens by 2004. In 2009, an estimated 82 pairs were alive; this number decreased to 41 until 2017 due to drought in Southern California.

References

{{Taxonbar, from=Q15708256 Lanius Endemic fauna of California Endemic birds of the Western United States Fauna of the Channel Islands of California Fauna of the California chaparral and woodlands Natural history of Los Angeles County, California Endangered fauna of California Native birds of the Western United States