Less migratory and less irruptive than its more widespread cousin the American Goldfinch, Lesser Goldfinch is nonetheless a common sight in much of the western United States. It is most prevalent in more southerly areas where it occurs year-round, such as west Texas, New Mexico, Arizona, and California.
In April and May watch for the slight northward pulse of the more northerly breeding birds (which reach northern Colorado and southern Idaho). Fall migration in October results in a contraction of the range and a concurrent increase in occurrence in the south as many of the birds pass right on through to winter in northern Mexico. Like the Rock Wren, the passage of Lesser Goldfinch, is often ignored since the migrations of longer-distance migrants like Western Tanager and Swainson’s Hawk are so much more dramatic and obvious. We hope to study some of these species in more detail in the coming years, thanks to your eBird reports.
NOTE: This STEM map is a bit over-ambitious in its predictions, showing the species north into central Wyoming and Montana, both areas where Lesser Goldfinches are exceedingly rare. This highlights the biases in the eBird dataset, which has lots of data from the Front Range of Colorado but a comparatively paltry amount from Wyoming and eastern Montana. Any help bolstering the eBird data from here would be welcome and would help to make these models “smarter”.