Lehigh Valley bird sightings for the week of December 18

Rusty Blackbird

A fairly unusual blackbird was reported this week: a Rusty Blackbird. They are seen occasionally in the Lehigh Valley, but this is the first reported since March 1.

The Rusty Blackbird is a bit larger and longer-tailed than the Red-winged Blackbird; its tail is shorter and its bill slimmer than the Common Grackle. The Rusty Blackbird is ecologically distant from other blackbirds. It is of medium size with a medium-length tail.

At this time of year, the male is black but its feather edges are a rusty brown. The female is gray-brown but also has rusty feather edges. Both sexes have pale yellow eyes.

During the summer breeding season, they are found in boreal wetlands in northern Canada. Winter will find them in wooded wetlands in the eastern and southeastern United States. You probably won't see them at a backyard bird feeder.

Once abundant, the species unfortunately is in decline. The population has plunged by at least 85 percent over the past 40 years, according to the Cornell Lab of Ornithology. Researchers aren't sure why. Some speculate that higher concentrations of mercury in their breeding grounds harms eggs and fledglings. Other possible explanations include changes in logging, agricultural practices, loss of habitat in wintering grounds and drier wetlands due to climate change.

A single Rusty Blackbird was seen in Williams Township, Northampton County, on December 16, according to a report sent to Dave DeReamus, of the Eastern PA Birdline. The Birdline is sponsored by the Lehigh Valley Audubon Society.

Other reports coming in during the week of December 18 found several instances of Pine Siskins. This seems to be a good year for Pine Siskin sightings. The birds may be seen in numbers in one year, then not at all in others. Click here for more information on this interesting bird and how it copes with the winter.

Plainfield Township, Northampton County
(at the Grand Central landfill)
Iceland Gull, 2 on December 13; 1 on December 16.

Williams Township, Northampton County
Rusty Blackbird, 1 on December 16.

Green Lane Reservoir, Montgomery County
(at the Church Road area)
Greater White-fronted Goose, 2 from November 27 to at least December 14.

Unami Creek Valley, Montgomery County
Pine Siskin, 4 on December 16.

Tinicum Park, Bucks County
Pine Siskin, 25 on December 12.

Peace Valley Park, Bucks County
Lesser Black-backed Gull, 83 on December 11.
Gray Catbird, 1 on December 11.

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