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The loggerhead shrike's historical range included much of
southern Manitoba from the north end of Lake Winnipegosis to
Whiteshell Provincial Park. Found in grassy areas near scattered
trees and shrubs, nesting populations are now primarily
concentrated in grasslands, shrubby areas or in the vicinity of
shelterbelts in extreme southwestern Manitoba, with occasional
nesting records south to Riding Mountain National Park, and east
to the southern Interlake and Winnipeg. Populations in
southeastern Manitoba are generally believed to belong to the more
endangered migrans subspecies, which has undergone significant
declines throughout its range and is primarily represented in
Manitoba by a small nesting population near Winnipeg.
Loggerhead shrike populations continue to decline throughout
North America and in Manitoba. Over 300 nesting pairs were
recorded in Manitoba as recently as 1993, but surveys from 1999 to
2001 revealed only about 100 known nesting pairs per year. While
cool, wet stretches since 1993 have severely hampered nesting
success and contributed to recent declines, a combination of
limiting factors are ultimately blamed for the species’ decline.
These include decreased habitat quality due to outright loss,
fragmentation and degradation of hunting, nesting and wintering
habitat and increased losses of young and adults to predators,
collisions with vehicles, pesticides, and other limiting factors
on nesting areas, the winter range and on migration.
Monitoring, habitat enhancement and public awareness of this
species has been carried out by Manitoba Conservation since the
mid-1980s. A Recovery Action Group was recently formed for
loggerhead shrikes in southeastern Manitoba to promote public
awareness, increased monitoring, and to work with landowners and
interest groups to protect and enhance nesting habitat in
southeastern Manitoba. Currently considered Endangered under the
Manitoba Endangered Species Act, the loggerhead shrike is in
danger of becoming extirpated in this province.
For more information on the loggerhead shrike,
please see the Conservation
Data Centre Field Guide or view the Manitoba's
Species at Risk brochure (PDF document, 181 KB). |