Wednesday, February 15, 2012

Gray Jay

Because Gray Jays are found across North America's northern forests, they were once known as Canada Jays. Their range, however, drops into northern New England, Wisconsin, Minnesota, the northern Rocky Mountains, and the Pacific Coast of the United States. Others name this jay Camp Robber, as the bird readily raids campsites for food scraps, even off picnic tables.

Gray Jays thrive in frigid northlands. They nest in late winter. Eggs are incubated at temperatures of -30 degrees C! They do not even attempt a second brood in the seemingly more benign weather in May. Instead they rely on hoarded cashes of food glued to the undersides of tree bark and lichens. The Gray Jay's salivary glands are enlarged, thus the bird has plenty of spit to use as glue!

In these years of climate warming, Gray Jay numbers are declining at the southern end of their range. Ornithologists speculate that this trend is caused by their food cashes thawing and rotting and, thus, not being available during their late winter breeding season (Strickland and Ouellet 2011).

Notice the white feather shafts on the Gray Jay's back in the bottom photograph. These streaks are present only in Gray Jays in British Columbia south to northern California. Until at least 1931, these birds were thought to be a separate species, the Oregon Jay. The photograph was taken at Crater Lake National Park in southern Oregon.

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