Loggerhead Shrike

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Loggerhead Shrike
In Texas, USA
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Laniidae
Genus: Lanius
Species: L. ludovicianus
Binomial name
Lanius ludovicianus
Linnaeus, 1766

The Loggerhead Shrike (Lanius ludovicianus) is a passerine bird. It is the only member of the shrike family endemic to North America; the related Northern Shrike (L. excubitor) occurs north of its range but also in the Palearctic.

Loggerhead Shrike florida RWD6.jpg

The bird has a large hooked bill; the head and back are grey and the underparts white. The wings and tail are black, with white patches on the wings and white on the outer tail feather. The black face mask extends over the eye, unlike that of the similar but slightly larger Northern Shrike.

The bird breeds in semi-open areas in southern Ontario, Quebec and the Canadian prairie provinces, south to Mexico. It nests in dense trees and shrubs. The female lays 4 to 8 eggs in a bulky cup made of twigs and grass. There is an increase in average clutch size as latitude increases.

The shrike is a permanent resident in the southern part of the range; northern birds migrate further south.

The bird waits on a perch with open lines of sight and swoops down to capture prey. Its food is large insects, small birds and lizards.

Known in many parts as the "Butcher Bird," it impales its prey on thorns or barbed wire before eating it, because it does not have the talons of the larger birds of prey. The bird decorates its impaled victim with feathers and bills in order to attract a mate.[2]

The population of this species has declined in the northeastern parts of its range, possibly due to loss of suitable habitat and pesticide use.

"Loggerhead" refers to the relatively large head as compared to the rest of the body.

Conservation status[edit]

The Eastern Loggerhead Shrike (L.l. migrans) is critically endangered in Canada. (Although only one island subspecies is legally listed as endangered in the United States, the species is declining continentwide and no longer occurs in most of the northeastern U.S.)[3] A captive population was established at the Toronto Zoo and McGill University in 1997. In 2001 an experimental field breeding and release program managed by Wildlife Preservation Canada was established. "Field breeding" refers to moving captive pairs from their wintering cages at the Toronto Zoo and McGill to large enclosures within shrike habitat in Ontario where the pairs nest and raise their young and then the young are released to the wild when they'd naturally disperse from their parents. Since 2004, over 90 young have been released annually and between 2% and 6.5% of young released have successfully migrated and returned to breed in the subsequent year.[4] [5]

Subspecies[edit]

There are ten recognized subspecies of Loggerhead Shrike:[6]

  • Lanius ludovicianus anthonyi
  • Lanius ludovicianus excubitorides
  • Lanius ludovicianus gambeli
  • Lanius ludovicianus grinnelli
  • Lanius ludovicianus ludovicianus
  • Lanius ludovicianus mearnsi (San Clemente loggerhead shrike)
  • Lanius ludovicianus migrans
  • Lanius ludovicianus nelsoni
  • Lanius ludovicianus sonoriensis

References[edit]

  1. ^ BirdLife International (2012). "Lanius ludovicianus". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013. 
  2. ^ http://birds.audubon.org/species/logshr
  3. ^ Yosef, Reuven. 1996. Loggerhead Shrike (Lanius ludovicianus), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/231 doi:10.2173/bna.231
  4. ^ "Toronto Zoo > Conservation > Birds". Retrieved 2009-09-22. 
  5. ^ Wildlife Preservation Canada
  6. ^ http://www.catalogueoflife.org/col/details/species/id/11911366/source/tree

External links[edit]