Thursday, January 17, 2013

in decline: grosbeaks

And speaking of bird species in decline. Nature is always in a state of flux.

There was a time in the 1980s, when flocks of evening grosbeaks would spend their winters in the Tennessee Valley and foothills of the Great Smokies near my boyhood home in Gatlinburg. But, not any longer. Nope.

In 2007, the Audubon Society reported that their population had declined 78 percent in the past 40 years. Yet, this is not the first significant change in their numbers as the Audubon article penned by Greg Butcher continued, "The evening grosbeak teaches us how bird populations can change dramatically. Virtually unknown east of the Mississippi River until 1850, it expanded east—peaking in the mid-1980s—then plummeted. It's future will depend on maintaining healthy habitat in the boreal forest."

Historically, the eastern spread of the large, chunky yellow finches is possibly due to plantings of Manitoba maples and other trees and shrubs around farms and the availability of bird feeders in winter.

Their decline? In part, it is believed that the "chemical control of spruce budworm and other tree pests reduces this species' food supply and may cause secondary poisoning." 

Here one day, gone the next, such is the case with us all.

- Photo by Simon Pierre Barrette

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