The Pine Siskin is a small passerine bird that measures about 4.5 to 5 inches in length and weighs between 0.4 and 0.5 ounces. They have a short, conical bill and a forked tail, which makes them easy to recognize in the field. Pine Siskins have a streaked brownish-gray plumage on their backs and a yellowish-green tinge on their sides and underparts. They also have distinct wing-bars, which are pale yellow and black.
During the breeding season, Pine Siskins are found in boreal and montane forests across North America. They build their nests in conifer trees, and their breeding range extends from Alaska and northern Canada to the western United States. During the winter, Pine Siskins undertake irruptive migrations, which are unpredictable and driven by food availability. They may appear in large flocks in areas where they are not usually seen, such as the southern United States, Mexico, and Central America.
One of the distinguishing features of the Pine Siskin is their preference for seeds as their primary food source. They have a particularly strong affinity for conifer seeds, especially those of spruce, pine, and fir trees. Pine Siskins have been known to visit backyard bird feeders, especially during irruptive years, where they may feed on sunflower seeds, nyjer, and other small seeds. Their diet also includes insects and tree sap, particularly during the breeding season.
Male and female Pine Siskins look very similar, but males tend to have more intense and brighter yellow wing-bars than females. Pine Siskins are often found in flocks, which can consist of both adults and juveniles. In addition to their distinct appearance, Pine Siskins are also known for their high-pitched, trilling calls, which can be heard as they fly overhead.
In conclusion, the Pine Siskin is a small, streaked bird that is found in boreal and montane forests during the breeding season and undertakes irruptive migrations during the winter. They have a preference for conifer seeds as their primary food source and are often found in flocks. Their distinct appearance, high-pitched calls, and unpredictable migrations make them a fascinating species to observe and study.