Lawrence’s Goldfinch (Carduelis lawrencei), is a small songbird that ranges irregularly throughout southwestern North America. It is known for its wandering habits. It breeds from about Shasta County, California to northern Baja California, largely in the Coast Ranges and the foothills of the Sierra Nevada and in the Baja highlands, but also sometimes as far down as the coast. There are only a few places where it has been observed to nest annually, notably the Carmel Valley and the South Fork Kern River. Choice of areas in its breeding range may depend on climate through the availability of water and preferred foods. Movements to the coast and upslope in the Sierras occur in drought years and movements to the edges of the range and into the Central Valley after wet years, possibly because of an increased food supply. It has bred a few times in Arizona.
Most, but not always all, birds leave northern, central, and inland southern California in winter. They move into the coastal lowlands and into the lower parts of the southeastern California deserts, ranging irregularly southeastward to northern Sonora and northwestern Chihuahua and eastward to the southern half of Arizona, southwestern New Mexico, and even the area of El Paso, Texas. In some years mysteriously few birds are observed in winter; possibly the birds are in Sonora and Chihuahua, which are poorly covered by naturalists. The typical nesting habitat is dry and open woods that are near both brushy areas and fields of tall annual weeds, usually within half a mile of a small body of water. It may nest in other habitats, including rural residential areas, but not in deserts or dense forests. Outside the nesting season it occurs in many open habitats including deserts, suburbs, and city parks.
At about 4.75 inches long and weighing about 11.5 grams (0.4 oz) it is slightly bigger than the Lesser Goldfinch and slightly smaller than the American Goldfinch, with less yellow in the plumage than either. Adults of both sexes are gray with pink to grayish flesh-color bills, stubbier than other goldfinches’. They have yellow rumps and paired yellowish wing-bars, as well as yellow edges on the flight feathers and yellow on the breast. The tail is black, crossed by a white band. Plumage is duller in winter, brightening after a spring molt. Males are paler, with black caps and faces and larger areas of brighter yellow. Females are browner, have less and duller yellow, and lack the black. Juveniles resemble females but are even duller and have faint streaks on the upperparts and especially the underparts.
Lawrence’s Goldfinch feeds almost entirely on seeds of shrubs and forbs. During the nesting season, it eats seeds of annuals, strongly favoring the Common Fiddleneck or Rancher’s Fireweed. Birders seeking Lawrence’s Goldfinch are advised to know this plant. At other seasons in California, it predominantly eats Chamise or Greasewood and also berries of mistletoe and Coffeeberry or California Buckthorn. In Arizona, it often eats the seeds of pigweeds or amaranths and Inkweed.. It is also attracted to niger seed at feeders.
The nesting season is early spring to early summer, or sometimes as late as late July. Pairs form in large pre-breeding flocks. Pairs leave the flocks and search for nest sites, the female taking the lead, often carrying nesting material and making building motions. The male follows, singing and calling. The nest site may be in any of a number of trees, but early in the season it is often in mistletoe or Western Sycamore, while later it is in live oaks and especially the deciduous Blue Oak. Nests are usually single but sometimes in loose colonies that may contain over 10 pairs. The female builds the nest while the male follows her on long material-gathering forays or sings from a perch. It is a loosely woven cup in a fork of several small branches, placed about 10 feet up near the edge of the tree. There are three to six eggs, unmarked white with a blue or green tinge.
The female incubates for 12 to 13 days and broods the chicks for four or five days, staying almost constantly on the nest while the male hunts for and brings food. After the fourth day, the female joins the male in food-gathering trips but still broods at times through the seventh day. The chicks fledge at about 13 or 14 days, and after another 5 to 7 days leave the family to join a pre-migratory flock. During the breeding season, males join to form small flocks while females are on the nest. At other times, birds are found in flocks that typically comprise under 50 individuals but are occasionally over 500. Flocks may mix with other small seed-eating species.