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.

The 12 days (or so) of Christmas

Gray Partridge

Birds are mentioned in many songs, including the "Twelve Days of Christmas." The song is an English Christmas carol that enumerates a series of increasingly grand gifts to be presented during the 12 days between Christmas Day and the day before the Feast of the Epiphany, which is January 6. 

The song, first published in England in 1780 as a chant, may have been French in origin. In 1909 an English composed put the words to music using a traditional folk melody.

So what are those birds that are part of this big package of gifts?

A Partridge in a Pear Tree. According to the Cornell Lab of Ornithology, the partridge in North America is the Gray Partridge, which was introduced from Eurasia. The bird is found in flat agricultural land along most of the United States-Canadian border. It is a small chicken-like bird with a short neck and tail. It has a grayish brown back and chest, with some chestnut barring on the flanks. The tail is chestnut colored. One of the most amazing facts about the Gray Partridge is the size of the broods. The hen may lay up to 22 eggs. Talk about a gift that keeps on giving!

Ringed Turtle-Dove

Two Turtle-Doves. The Ringed Turtle-Dove has been domesticated for so long that its wild origins are not know for certain. Feral populations have become established in some cities in the southern United States. They are related to Mourning Doves and common street pigeons. The Ringed Turtle-Dove seems to have lost the fear of large, strange or moving creatures with the exception of predatory birds. They will still "freeze," which is helpful when their pale color is contrasted with a lawn.

Three French Hens are "Favorolles" or chickens. Enough said.

Old World Common Blackbird

Four Calling Birds. This gets trickier. These are the Common Blackbirds, part of the thrush family, found throughout most of Europe. They are not necessarily what we know as blackbirds. The Old World male is all black, with yellow eye-ring and bill, and has a rich melodious song. These birds are omnivores, eating insects, earthworms, berries and fruits.

New World blackbirds are part of the Icterid family, which includes grackles, orioles, meadowlarks, cowbirds and Bobolinks. However, these are not evolutionary close to the Old World thrushes.

Six Geese a-Laying. Domesticated geese have been kept for their meat, eggs and down feathers since ancient times. Physically they are different from wild geese, often weighing almost twice as much. Wild geese have a more horizontal posture and a slim rear end. Domestic geese lay down large fat deposits toward the tail, forcing them into a more vertical posture. This also prevents flight although geese will run and flap their wings when startled. Females lay almost 50 eggs per year, almost four times as many as wild geese.

Mute Swan

Seven Swans a-Swimming. The swans in the carol are probably Mute Swans, which are native to northern and central Eurasia. They were introduced to North America to grace ponds of parks and estates. Mute Swans have black masks above their orange beaks. Mute Swans are somewhat aggressive in locations where they have escaped from their owners and established their own breeding populations. They will disrupt the nesting of native waterfowl. Some states are attempting to control Mute Swan populations.

Wild native swans in North America are Trumpeter Swans or Tundra Swans. Both are white-bodied. 

Trumpeter Swans have black beaks and black face masks. These are the largest North American waterfowl. These swans were hunted for their feathers into the late 1800s, causing a tremendous decline in numbers. Trumpeter Swans mate for life and can live a long time, some longer than 24 years.

Tundra Swans have a black bill and face but they are smaller birds. They breed on the North American tundra and, in the east, winter along the Atlantic Coast and Great Lakes.

The Rusty Blackbird is in serious trouble

Male Rusty Blackbird

Researchers are becoming increasingly concerned that the population of Rusty Blackbirds is plummeting and they're not certain why. They're asking birders to help count the migrating birds so they can obtain a clearer picture of what's wrong.

The Cornell Lab of Ornithology calls the Rusty Blackbird "one of North America's most rapidly declining species." Formerly abundant, the population has plunged by at least 85 percent over the past 40 years.



The Rusty Blackbird is a medium-sized blackbird with a slender bill and a medium-length tail. In winter, the male is distinguished by its rusty brown feather edges, pale yellow eye and buffy eyebrow. The female is gray-brown. It also has rusty feather edges, pale eyes and a bold eyebrow, contrasting with darker feathers right around the eye.

The bird is a bit larger and longer-tailed than the Red-winged Blackbird (with its brilliant red wing patch) and a shorter tail and slimmer bill than the Common Grackle. It shares the pale yellow eye of the grackle. If you listen closely to the sounds of a large blackbird flock, you may hear their song: a gurgling, creaky sound like a rusty-hinged gate being opened.

Female Rusty Blackbird

Rusty Blackbirds are ecologically distant from other blackbirds. You won't see them at a backyard feeder. In the summer breeding season in northern Canada, they are found in boreal wetlands. Winter will find them in wooded wetlands in eastern and southeastern United States.

The birds have been seen in the Lehigh Valley this autumn and winter. The Eastern PA Birdline, a project of the Lehigh Valley Audubon Society, reported sightings at 11 different locations this season, especially in Upper Mount Bethel Township, Northampton County. The first sightings came on September 25, 2013; the latest occurred during the week of February 28. Most leave the Lehigh Valley by late April.

Researchers have been investigating the causes of the population decline. They've found that Rusty Blackbirds in their breeding grounds have mercury concentrations three to four times than those found elsewhere. The feathers give one indication: Mercury levels return to normal in the winter but soar during breeding season in Canada. The mercury harms breeding, leaving fewer fledglings. Other possible explanations include changes in logging, agricultural practices, loss of habitat in wintering grounds and wetlands drying due to climate change.

Researchers this week began asking you to report birds in your woods and wetlands. Cornell ornithologists have partnered with other organizations to coordinate a Rusty Blackbird Migration Blitz—a continent-wide effort to track Rusty Blackbirds.

To learn more about this project and find out how you can contribute your sightings, go to the International Rusty Blackbird Working Group at www.rustyblackbird.org. Make sure you hurry, though. The Rusty Blackbird migration in the Lehigh Valley is drawing to a close.