98:15:38 is serious

The Loggerhead Shrike (Lanius ludovicianus) is the only exclusively North American species of a largely Afrotropical family of birds. Although generally regarded as a full species, some authorities regard it as a race of the similar Northern or Great Gray Shrike (L. excubitor), the only

’ ‘? other shrike found in Canada. In ' Canada, it is primarily a breeding bird of the prairie portion of the prairie provinces and of the agri- cultural belt south of the Great Canadian Shield in southeastern Ontario, southern Quebec and New Brunswick, with few records in British Columbia and rare nesting in Nova Scotia.

It's decline in Ontario was noted about the same time that the blue list of North American birds showing non—cyclical declines was first published, a list on which the spe-

cies appeared annually, with declines as sharp

as 70% reported insome areas. Recent analyses

of Christmas Bird Count data and Breeding Bird

“I Survey data have strongly supported the "blue list" desig—

' nation for North America as a whole, with minor bright spots

'5 in southern and western portions of its range in the U.S. A

recent status study in Canada recommended that it be classed as Threatened in Canada, a designation adopted by the Committee on

the Status of Endangered Wildlife in Canada (COSEWIC) in April 1986.

Documentation of such declines in Canada relies primarily on Breeding Bird Survey data and impressions of regional experts. The stronghold of their breeding population in Canada remains on the prairies, where im— pressions of a decline are widespread. In Alberta, the Edmonton Bird Study Group listed the Loggerhead Shrike among species recommended for a pro— vincial risk list, and although Breeding Bird Survey data from 1966 to 1979 did not show a significant decline in statistical terms, a comparison of 1972-1977 data with figures from 1978-1983 suggests sharp reductions in both southern and central areas. In Saskatchewan, Breeding Bird Surveys average the highest numbers of shrikes per route in Canada, but declines are at a statistically significant level. In the Saskatchewan portion of the Qu'Appelle Valley and deifinite decrease in numbers since about 1957 was noted. The one~bright spot on the prairies appears to be in the extreme southeastern corner of Saskatchewan and southwestern corner of Manitoba.

Breeding bird survey data show a significant decline in Manitoba, Ontario, and few birds are now even sighted annually in Quebec.

The species was evidently never common in the New Brunswick portion of its breeding range and has not been recorded in the Breeding Bird Sur— vey there in recent years. Its Nova Scotia range was at best very localized and probably temporary.

The chief cause(s) of the steady decline of Loggerhead Shrikes remain obscure today. The chief suspects appear to be loss of habitat and chemical contamination, possibly in combination. Natural factors such as predation,

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