Tag Archives: sexual dichromatsim

Pine Siskin ~ Carduelis pinus

Pine Siskin ~ Carduelis pinusPine Siskin ~ Carduelis pinus

We certainly weren’t expecting to see and hear a new-to-our garden species of birds flocking to the Nyjer seed feeder on a frigid mid-January day. American Goldfinch in size, the richly mottled plumage resembled something closer to a sparrow. Their delightful birdsong was new and fresh to my ears and sweetly cheering. Currently in residence is a flock of House Sparrows, with several Song and Savannah Sparrows tagging along, but I had no success with identifying this new entourage when thumbing through the sparrow section of Audubon’s books. Returning to the goldfinch pages, Pine Siskins are closely related to American Goldfinches (the two species comprise the subgenus Spinus), and information was readily available, once on the right track.

To be sure, I emailed a snapshot to Chris Leahy at Mass Audubon and he confirmed that this was indeed a flock of Pine Siskins and that they are having an “irruptive” year. In ecological terms, irrupt is defined as “to increase rapidly and irregularly in number.”

Pine Siskins are “classic,” or true finches—small to moderately large, with twelve tail feathers and nine primary feathers, and strong conical shaped beaks designed to both penetrate the hard external shells of seeds and delicately extract a morsel of food. Members of the genus Carduelis sensu lato feed their young on a highly nutritious and easily digested diet of partially regurgitated, milky cereal-like blend of seeds.

Kingdom: Animalia

Phylum: Chordata

Class: Aves

Order: Passeriformes

Family: Fringillidae

Genus: Carduelis

(Sub) Genus: Spinus

Species: pinus (Pine Siskin)

Species: tristis (American Goldfinch)

Pine Siskins are primarily a northern species, whose irruptive winter activity in the United States occurs in years when seed crops have failed in the boreal forests. Ornithologists believe the severity of winter weather in northern parts of the siskins’ range, as well as factors not completely understood, also contribute to their irruptive cycles. The siskins’ principal foods are the seeds of alder, cedar, birch, hemlock, and a variety of conifers. Occasionally, large flocks will appear as far south as Florida. Protecting coniferous forests will help protect the Pine Siskins.

Nimbly dangling upside down and every which way to feed, battling for a place at the feeder, and seemingly unafraid of my approach with camera in hand, the gregarious Pine Siskins are a fascinating species to observe. I am so glad I took a few snapshots when I did. Today it is snowing, again, and the temperatures are hovering around freezing. Perhaps they will stay (we keep the Nyjer seed feeder well stocked) or perhaps they will continue migrating further south.

Pine Siskins typically breed in coniferous forests. Although monogamous, they nest in both isolated pairs and loose colonies, and pairs may visit one another’s nests. The female constructs the nest on a horizontal branch of a conifer, well hidden and well away from the trunk.The nest resembles a large shallow basket, is watertight, and built of twigs, grass, rootlets, strips of bark, lichen, and leaves, and lined with moss, plant down, feathers, and hair. The female incubates the eggs for about two weeks, rarely leaving the nest. The male brings her food while she incubates and for the first few days after the young hatch. The fledglings leave the nest in approximately two weeks. The male and female continue to feed the young for several more weeks.

Because Pine Siskins forage in flocks and nest in loose colonies, they are particularly susceptible to salmonella. It is important to keep Nyjer seed feeders (all bird feeders) scrupulously clean. Scrub inside and out weekly with a solution of vinegar and water.

American Goldfinches display a dramatic example of sexual dichromatism in their plumage; during breeding season the males molt to brilliant cadmium yellow while the females maintain their olive hue year round. Pine Siskins show a more subtle form of sexual dichromatism. The male is typically identified by yellow patches in the wings and tail feathers. The female shows much less yellow. Sexual dichromatism is the systematic difference in color form between male and female in the same species (Greek, di meaning two, and chromatic relating to color). The yellow color of the pine siskins is not always clearly visible when perching and they are often mistaken for sparrows, with their similar brown, heavily streaked underparts.

Friday is my well-guarded, sacred day to paint, and I am currently finishing my illustrated book about butterflies. If I can’t manage to squeeze in any other time during the week to paint, at least I know I will have my Friday. My painting area is arranged beneath a northeast- facing window, ideal light for painting flora and fauna as the light coming through the left side evenly illuminates the subject placed on the table. Several of the bird feeders hang a mere ten feet from the window and are a wonderful source of distracting entertainment. Today at the bird feeders we observed the flock of Pine Siskins, a Dark-eyed Junco and his Song Sparrow friend (an oddly matched pair who always appear to come and go together), American Goldfinches, Blue Jays, Harrier Hawk, a pair of Northern Cardinals, one Carolina Wren, and the ubiquitous House Sparrows. A Northern Mockingbird, lately joined by an American Robin, comes daily to the winterberry and hollies, helping themselves to only a few berries, and then departing. The days are growing longer; we’re half past January, we only have February to get through, and soon we will be welcoming spring. I am looking forward to black earth revealed, new notes of fresh scents, and the chorus of courting songbirds.