Bird of the Week

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Photo courtesy Charles Martinez

This week’s Bird of the Week, compliments of the Weminuche Audubon Society and Audubon Rockies, is the MacGillivray’s warbler.

It’s warbler season and time to enjoy those colorful songsters who spend the summer here. Don’t focus your binoculars high to find this wood warbler that spends most its time in dense underbrush, usually in riparian areas. Here it forages on the ground or on low leaves, and on the branches of shrubs for a wide variety of insects. It is rarely found more than 6 feet from the ground.

Males sing frequently during breeding season to defend nesting territories typically two to four acres in size. Both sexes often give a tsik call note while foraging. Knowing the calls and songs is a great help in trying to locate these and other warblers.

Male and female MacGillivray’s warblers are olive colored above and yellow below, have a gray hood extending to the chest and have white crescents above and below the eyes. A male’s coloring is bolder and he has dark patches around the eyes and on the chest that are lacking in females and immatures.

Birds are sometimes named for the person who first describes them. This bird was originally named the Tolmie’s warbler, but was renamed by John James Audubon to honor his friend and editor, William MacGillivray. This is the name that stuck.

Population numbers of these warblers have declined by more than 50 percent in the last 50 years. Forest management that preserves and creates semi-open habitat with shrubby areas favors the MacGillivray’s warbler.

For information on future events, visit www.weminucheaudubon-org and www.facebook.com/weminucheaudubon/.