The Lesser Goldfinch (Spinus psaltria) is a small songbird native to western North America. As its name suggests, it is closely related to the American Goldfinch, but is noticeably smaller in size, which is why it is referred to as “lesser”.
Opening Summary
The Lesser Goldfinch is called “lesser” because it is distinctly smaller than its relative, the American Goldfinch. Some key points:
- The Lesser Goldfinch measures only 4.3-5.1 inches in length and weighs 0.4-0.5 oz, while the American Goldfinch is 4.7-5.5 inches long and weighs 0.6-0.7 oz.
- The Lesser Goldfinch has more restricted breeding and year-round ranges, centered on the southwestern United States and Mexico, while the American Goldfinch is widespread across North America.
- “Lesser” distinguishes it from the superficially similar American Goldfinch and reflects its small size relative to that species.
Detailed Explanation
The Lesser Goldfinch belongs to the genus Spinus in the finch family Fringillidae. Its closest relative is the American Goldfinch (Spinus tristis), which it strongly resembles in coloration and shape. However, the Lesser Goldfinch is distinctly smaller, with males measuring 4.3–5.1 inches (11–13 cm) long and weighing 0.4–0.5 oz (11–14 g), compared to 4.7–5.5 inches (12–14 cm) and 0.6–0.7 oz (17–20 g) in American Goldfinch males. Females of both species are similarly proportioned relative to males.
This moderate but consistent size difference forms the basis for the Lesser Goldfinch’s common name. Adding the descriptor “Lesser” distinguishes it from its close cousin and indicates its small stature relative to the American Goldfinch. The terms “Lesser” and “American” allow clear communication about which species is being referred to.
Species | Length (in) | Weight (oz) |
---|---|---|
Lesser Goldfinch Male | 4.3-5.1 | 0.4-0.5 |
American Goldfinch Male | 4.7-5.5 | 0.6-0.7 |
In addition to its smaller size, the Lesser Goldfinch has a more restricted range and habitat preferences that separate it from the widespread and adaptable American Goldfinch. The Lesser Goldfinch breeds primarily in the southwestern United States and Mexico, wintering as far south as western Panama. It is common in deserts, shrublands, woodlands, and savannas, where it feeds on seeds from grasses and shrubs. Meanwhile, the American Goldfinch is found throughout most of North America in a variety of open and semi-open habitats.
Behavioral and Ecological Differences
Beyond physical size and geographic distribution, the two species exhibit subtle differences in behavior and ecology:
- Lesser Goldfinches are more social, foraging and migrating in large flocks.
- Their flight is more undulating due to their shorter wings.
- They begin breeding later in the year than American Goldfinches.
- Their nests are neatly woven from plant fibers and placed in the fork of branches, whereas American Goldfinches have messy nests placed further out on branches.
These differences in nidification and flocking habits likely reflect adaptations to the more arid southwestern environment occupied by the Lesser Goldfinch.
Taxonomy
The Lesser Goldfinch was first scientifically described in 1852 by Spencer Fullerton Baird under the scientific name Spinus psaltria. Its genus Spinus includes the American Goldfinch and other North and South American finch species. Although some taxonomists previously placed the Lesser Goldfinch in the genus Carduelis, genetic analysis supports a close relationship with Spinus finches.
Origin and History of “Lesser” Name
The term “Lesser” in the Lesser Goldfinch’s common name follows a convention for distinguishing smaller relatives of birds that share the same general name. Other examples include:
- Lesser Scaup (a small diving duck)
- Lesser Yellowlegs (a sandpiper)
- Lesser Whitethroat (a small warbler)
This naming pattern using “Lesser” originated from comparisons made by early ornithologists between related species and their desire to highlight their relative sizes. Scientifically describing and cataloging birds required a standardized nomenclature.
The earliest known use of “Lesser” in the Lesser Goldfinch’s name dates back to 1874 in the seminal History of North American Birds by ornithologists Baird, Brewer, and Ridgway. They used “Lesser Goldfinch” to distinguish it from the superficially similar but larger American Goldfinch, a convention which continues today.
Unique Identifying Traits
The use of “Lesser” in its common name immediately tells observers that the Lesser Goldfinch is a smaller version of the American Goldfinch. However, the two species can be reliably distinguished by more than just size:
- The Lesser Goldfinch has a shorter, stubbier bill than the American Goldfinch.
- Males have a black forehead, white rump patch, and more extensive yellow on the breast.
- Females lack the bright yellow plumage of female American Goldfinches.
- Their flight call is a flat, rapid twittering compared to the drawn-out “per-chik-o-ree” of the American Goldfinch.
Their smaller size simply provides a convenient shorthand for identifying Lesser Goldfinches in the field. Careful observation will reveal additional subtle differences in plumage, vocalizations, bill shape, and behavior.
Conclusion
In summary, the Lesser Goldfinch earns its common name by being distinctly smaller than its closest relative, the American Goldfinch. Early ornithologists used the term “Lesser” to highlight this size difference and distinguish between the two similar species. While not the most creative name, “Lesser” succinctly communicates the essence of how this species compares to the American Goldfinch in a naming convention widely used for many types of birds. Beyond just size, a careful observer can identify a number of more subtle anatomical and behavioral features that differentiate Lesser Goldfinches from the widespread and familiar American Goldfinch.