The California Gnatcatchers, Polioptila californica, are non-migratory residents with a limited range, extending north from Mexico’s Baja California to coastal southern California, where they remain year-round depending on a variety of scrub habitats.
This species was recently split from the similar Black-tailed Gnatcatcher of the Sonoran and Chihuahuan deserts.
They are inconspicuous as they are perfectly camouflaged by their plumage and they are most often heard rather than seen.
Status
Their specific habitat requirements make them vulnerable and they are focal species in many regional habitat conservation planning efforts.
Even in the early 1900s, the population was described as being scarce and irregularly distributed but by the 1940s habitat was noticeably reduced.
In the U.S. loss of coastal sage scrub habitat has been estimated to be as much as 70-90%, with approximately 33% lost since 1993 when the species was federally listed as threatened.
There are ongoing efforts to preserve more open land in Southern California to help ensure that this species will not disappear from its former range.
Description
The California Gnatcatcher is a small, slender, gray, non-migratory songbird having a long, black tail with white tips and fine white edging. They are about 10.8 cm (4.25 inches) long. It has a long, thin black tail with narrow white tips and edges on the underside of the tail feathers.
A male in breeding plumage has a black cap, otherwise has a black line over the eye. Males are mostly gray with darker upperparts. After the breeding season, males obtain a plumage color like the females.
The female looks similar to the male, but she has a blue-grey crown instead of the black crown of the male. Females have more of a brown tone on the back, flanks, and belly.
Similar Species ID
The California Gnatcatchers make kitten-like mewing noises that distinguish them from the Black-tailed Gnatcatcher (Polioptila melanura). The California Gnatcatcher can also be distinguished from the Black-tailed by its darker underparts and less white on its tail. The other gnatcatchers: the Blue-gray and Black-capped, are larger with more white on their tails.
Ecology
The monogamous pairs tend to stay in the same locale. Both parents build nests, incubate, and care for the young. The nest site is established by a male who also initiates nest building. The cone-shaped nests are built in shrubs and first-brood eggs, consisting of 2 to 5 eggs, are laid in late March.
With a roughly 120-day breeding season, they may be able to have as many as three broods per season. A high rate of nest predation is compensated by up to ten re-nesting attempts over the long breeding season.
Young tend to disperse within ten km of their natal territory and find a mate within several months. Survival depends on winter temperatures and rainfall.
Song / Call
Its call sounds like a kitten’s mew (a rising and falling zeeeeer, zeeeeer).
Diet:
Their main food intake consists of arthropods, especially little leafhoppers, spiders, beetles, and true bugs.
