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EASTERN LOGGERHEAD SHRIKE
Lanius ludovicianus migrans
Original range | Current range | Estimated population | Threats to survival | Species recovery | Results | Partners and links
Description: Named for its disproportionately larger, or "logger" head, the Eastern Loggerhead Shrike is a medium-sized grey and white songbird, slightly smaller than a robin with black on the wings and tail and a black raccoon-like "mask" across its eyes. It is the only truly predatory songbird, using its slightly hooked beak to dispatch mice, voles, grasshoppers, beetles and other small prey. It is also unusual in the way it stores its food on thorns and barbed wire because it lacks strong talons or claws for grasping the prey it has killed.
Most Eastern Loggerhead Shrikes winter in the United States and migrate to Canada in April for the breeding season. Females lay five to seven eggs which they incubate while the males bring them food. Reproductive success is considered high. The eggs hatch about 15 days after laying, and both parents feed the young. Young shrikes have bright orange, featherless skin and yellow beaks and talons. They begin learning to fly just 18 days after hatching. The young continue to depend on their parents for another three to five weeks, as they learn to fly, forage and become independent.
Original range: Originally the range of the Eastern Loggerhead Shrike extended from Manitoba to New Brunswick and as far south as northeastern Texas, western North Carolina and Maryland.
Current range: Today, Eastern Loggerhead Shrikes are found in just five small isolated pockets in Manitoba and Ontario, They are no longer present in the Maritimes, while in Quebec, where they were once common, no birds have been found since 1995. They prefer open short grassland areas with few trees and thorny shrubs, using pasture areas for hunting.
Estimated population: It is believed there are only 100 pairs remaining in North America. In 2004, 36 wild pairs were found in Canada, 27 of those in Ontario.
Threats to survival: The causes of the persistent decline in Eastern Loggerhead Shrike populations are poorly understood. Perhaps the greatest threat to the Eastern Loggerhead Shrike is the loss and fragmentation of the short grassland they depend on. This is due to natural succession and recent changes in agricultural land use, particularly the conversion of pastures and hayfields to grow crops that involves removing the hedgerows, shrubs and trees that are essential to the shrike's lifestyle. Another potentially serious problem is motor vehicles. Eastern Loggerhead Shrikes often perch on fences and utility lines near roadways, and sometimes collide with passing cars and trucks. Pesticides may also be a factor.
Species recovery: The Eastern Loggerhead Shrike was listed as endangered by the Committee on the Status of Wildlife in Canada (COSEWIC) in 1991. A Loggerhead Shrike Recovery Team was formed in 1992. In 1996, the Team divided into a Western Loggerhead Shrike Recovery Team (for the "threatened" western sub-population) and an Eastern Loggerhead Shrike Recovery Team (for the endangered eastern sub-species). WPC's fieldwork consists of:
conducting annual surveys and monitoring the population
banding birds and asking people to report sightings to help us learn about their behaviour
breeding birds in captivity to protect the genetic diversity of the species and releasing them when conditions are right in order to boost wild populations
conducting genetic studies to learn more about shrike population dynamics
contacting landowners and helping them protect and enhance shrike habitat
working with agricultural associations, aggregate producers, conservation and naturalist associations and many others to protect and improve shrike habitat
liaising with American counterparts to establish a North America-wide recovery effort
Results: Our efforts are paying off: shrike populations are increasing, and thousands of acres of habitat have been restored or improved. In 2005, 25 pairs of wild shrikes in Ontario successfully fledged 66 young, while 34 captive pairs produced 59 young, of which 54 were released to the wild. In 2006 we unfortunately saw a decline in the wild population, down to 18 pairs in Ontario, fledging 63 young. However we had huge success with our captive pairs – 31 pairs produced 128 young, 111 of which were released to the wild. This is more than all previous years combined!
The capture of a captive-bred shrike in a mist net at the Long Point Bird Banding Station in September 2004, a month after it had been released on the Bruce Peninsula, proved that captive-bred birds instinctively know how to migrate south. In 2006, another young released in Dyer’s Bay that season was seen hunting near Long Point. Even more exciting was the discovery of a captive-bred female tending a nest with five young on the Carden Plain in May 2005. In 2006, a second captive-bred female returned to breed successfully with a wild male. This is strong evidence that shrikes born in captivity can successfully enter the wild breeding population.
For continuing updates, see the field reports on the right of this page.
What you can do to help:
Make a contribution today towards WPC's Eastern Loggerhead Shrike recovery activities.
If you are a landowner within the traditional breeding areas of the Eastern Loggerhead Shrike (in Manitoba, West St. Paul, the Red River Plain and the Interlakes; in Ontario, the Napanee Plain, Carden Plain, Smith Falls Plain, Grey and Bruce Counties, and Manitoulin Island; and in Quebec, the Outaouis), here's how you can help maintain or improve habitat for the shrikes:
Maintain existing pastureland and expand, if possible.
Maintain and plant trees and shrubs at the edges of pastures and fields.
Leave the odd snag (dead tree) standing.
Let cattle graze.
Avoid using pesticides on your land.
Avoid approaching nest trees, breeding birds and their young between April and the end of August.
Report sightings of Eastern Loggerhead Shrikes to the Recovery program's toll-free number, 1-800-956-8840.
Obtain "endangered species habitat" signs from the Recovery Team for posting on roads beside your property to encourage slower driving and reduce the possibility of road-kills.
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Eastern Loggerhead Shrikes
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