Lehigh Valley bird sightings for week of January 22

Male Mountain Bluebird (file photo)

Mountain Bluebirds are common in the West's wide-open spaces, where prairie grasses and sagebrush spread across the landscape. You'll see them hoving above the ground, looking for insects and then pouncing on their prey.

You're not supposed to see them in the Lehigh Valley. As a rule, they don't venture east of the Mississippi River. However, one hardy Mountain Bluebird has now spent a full month on private lands in Bucks County's Tinicum Township, not far from High Rocks State Park at Point Pleasant.

Fortunately the Mountain Bluebird eats some of the same wintertime foods that are often found in its normal range: cedar berries, elderberries and the seeds of sumac, mistletoe and hackberry. It will savor any insects it finds during occasional mild spells in winter.

Mountain Bluebirds breed in the Rockies and high plains from Colorado to British Columbia. They migrate relatively late in the fall and early in the spring. Their winter range varies depending on food supply. They could migrate as far south as Mexico. Others remain yearlong in the eastern foothills of the Sierra Mountains or in northern Arizona and northern New Mexico. Occasionally they stray from their normal winter range.

Mountain Bluebirds are sleeker and longer-winged than the Eastern Bluebirds that inhabit the fields of Pennsylvania. The males lack the orange breast and flanks of the Eastern Bluebird. Female Mountain Bluebirds are a dusky gray.

Female Mountain Bluebird; Jackson, Wyoming

As with Eastern Bluebirds, they nest in cavities of trees that grow along the edges of open fields. They also will use nesting boxes.

A male Mountain Bluebird has been seen in Tinicum Township along Tory Road, just east of Wormansville Road, from December 20 through at least January 21, according to Dave DeReamus, who compiles a listing of bird sightings in the Lehigh Valley region for the Eastern PA Birdline, which is sponsored by the Lehigh Valley Audubon Society.

Because the bluebird stays on private property, you can view it only from the road. Do not enter private land.

Here are other Lehigh Valley bird sightings for the week ended January 22.

Bangor, Northampton County
Blue Jay (a leucistic bird), 1 on January 15.

Plainfield Township, Northampton County
(at the Grand Central landfill)
Iceland Gull, 2 on January 16 (1 adult, 1 first-winter bird).

Beltzville State Park, Carbon County
Bonaparte's Gull, 2 on January 17.

Fogelsville Quarry, Lehigh County
Redhead, 1 on January 20.

Green Lane Reservoir, Montgomery County
Red-breasted Merganser, 1 on January 17.
Also seen: Common Goldeneye.

Peace Valley Park, Bucks County
Redhead, 1 on January 20 and January 21.
Greater Scaup, 3 on January 15.
Common Merganser, approximately 525 on January 16.
Also seen: Brown Thrasher.

To report bird sightings to Dave DeReamus, send an e-mail to becard@rcn.com with the word "Birdline" in the subject heading.