Friday, July 31, 2015

Loggerhead Shrike

On Wednesday, 29 July, John Holden and I drove up to the 180th Street Marsh in nearby Dakota County. Our goal was to photograph one of the breeding Loggerhead Shrikes reported off and on all summer. Previously, we made unsuccessful forays to the area—today we found this juvenal bird immediately upon our arrival, about a quarter mile west of the marsh.

Here in Minnesota, the Loggerhead Shrike is a rare, local, summer resident. Across all of North America, populations of these shrikes have declined due to the spraying of biocides, changes in agricultural practices, and competition form other bird species. Northern populations are migratory, replaced in winter by Northern Shrikes. One reason for this migratory behavior may be the Loggerhead’s reliance on an invertebrate diet.  Although varying regionally, invertebrates usually make up about 72% of what they eat. The remainder consists of vertebrates like small mammals and birds, reptiles and amphibians (Yosef 1996).

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