A Lesser Goldfinch

by Robert Bales

Title

A Lesser Goldfinch

Artist

Robert Bales

Medium

Photograph - Photo

Description

While I was enjoying the sunshine in the Foothills, Arizona, I found this Lesser Goldfinch resting on a branch in our front yard. It is the time of year as they are enjoying the winter before they migrate back to the North from the Southwest.

This petite species is not only the smallest North American Spinus finch, it may be the smallest true finch in the world. Some sources list more subtropical Spinus species as slightly smaller on average, including the Andean siskin. This species ranges from 9 to 12 cm (3.5 to 4.7 in) in length and can weigh from 8 to 11.5 g (0.28 to 0.41 oz). Among standard measurements, the wing chord is 5.5 to 7 cm (2.2 to 2.8 in), the tail is 3.9 to 4.7 cm (1.5 to 1.9 in), the bill is 0.9 to 1.1 cm (0.35 to 0.43 in) and the tarsus is 1.1 to 1.2 cm (0.43 to 0.47 in). There is a slight NW-SE cline in size, with the largest birds from Mexico and south being up to one-fifth larger than the smallest from the extreme NW of its range; this effect is more pronounced in females. There is also considerable variation in the amount of black on head and back in males, and thus three subspecies have been proposed. But this variation too seem to be simple and clinal changes in allele frequency, and thus the "subspecies" might be better considered morphs or geographical forms.
Males are easily recognized by their bright yellow underparts and big white patches in the tail (outer rectrices) and on the wings (the base of the primaries). They range from having solid black from the back to the upper head including the ear-coverts to having these regions medium green; each of the back, crown and ear regions varies in darkness rather independently though as a rule the ears are not darker than the rest. In most of the range dark psaltria birds (Arkansas goldfinch) predominate. The light birds are termed hesperophilus and are most common in the far western U.S. and northwestern Mexico.

Jabbering clouds of yellow, green, and black Lesser Goldfinches gather in scrubby oak, cottonwood, and willow habitats of the western U.S., or visit suburban yards for seeds and water. These finches primarily eat seeds of plants in the sunflower family, and they occur all the way south to the Peruvian Andes. Listen closely to their wheezy songs, which often include snippets from the songs of other birds.

Uploaded

March 6th, 2018

Statistics

Viewed 583 Times  -  Last Visitor from Wilmington, DE on 04/17/2024 at 10:47 AM

Colors

Embed

Share

Sales Sheet

Tags