Lawrence's Goldfinch
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| Carduelis lawrencei Cassin, 1852 |
Lawrence's Goldfinch, Carduelis lawrencei, is a small songbird that ranges erratically in southwestern North America.
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[edit] Description
At about 4.75 inches (12 cm) long and weighing about 0.4 oz (11.5 g), 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 (Sibley 2000, Oiseaux.net 1996-2007). Plumage is duller in winter, brightening after a spring molt (Davis 2001, Oiseaux.net 1996-2007). 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 (Sibley 2000, Oiseaux.net 1996-2007). Juveniles resemble females but are even duller and have faint streaks on the upperparts and especially the underparts. (Davis 2001, Oiseaux.net 1996–2007).
Calls include "a nasal too-err, also a sharp, high PIti and Itititi" (Sibley 2000). The flight call, which is diagnostic, is given as "a high, clear ti-too" (Sibley 2000) or tink-ul "reminiscent of glass wind-chimes" (Davis 2001). The song is high-pitched, continuous, and limited in frequency range, including wind-chime notes and especially imitations of other species' calls and other simple and distinctive sounds (Sibley 2000, Davis 2001). Males sing in winter but mostly in the breeding season. Females sing occasionally and briefly (Davis 2001).
[edit] Range and habitat
Lawrence's Goldfinch 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; its highest breeding altitude is about 8,800 feet (2,680 m) on Mount Pinos. 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 (Davis 2001).
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 (sometimes in large numbers) southeastward to northern Sonora and northwestern Chihuaha and eastward to the southern half of Arizona, southwestern New Mexico, and even the area of El Paso, Texas (Davis 2001)—roughly the Madrean sky islands region. 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 greatest eastward irruptions often occur in wet periods and are synchronized with irruptions of other seedeating birds such as the Red-breasted Nuthatch, the Red Crossbill, and the other North American goldfinches (Davis 2001).
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 (0.8 km) 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 (Davis 2001).
[edit] Behavior
[edit] Diet
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, Amsinckia menziesii var. intermedia. Birders seeking Lawrence's Goldfinch are advised to know this plant. At other seasons in California, it predominantly eats Chamise or Greasewood (Adenostoma fasciculatum) achenes and also berries of mistletoe (Phoradendron) and Coffeeberry or California Buckthorn (Rhamnus californica). In Arizona, it often eats the seeds of pigweeds or amaranths (Amaranthus) and Inkweed (Suaeda moquinii) (Davis 2001, 1999).
[edit] Breeding
The nesting season is early spring to early summer, or sometimes as late as late July. As in other cardueline finches, 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 (Platanus occidentalis), while later it is in live oaks and especially the deciduous Blue Oak (Quercus douglasii) (Davis 2001, citing Coutlee 1968a).
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 (3 m) up near the edge of the tree. There are three to six eggs, unmarked white with a blue or green tinge (Davis 2001).
The female incubates for 12 to 13 days and broods the chicks for four or five days, staying almost constantly on the nest; the male 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 about about 13 or 14 days, and after another 5 to 7 days leave the family to join a pre-migratory flock (Davis 2001).
[edit] Flocking
During the breeding season, males join in small feeding 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.
[edit] Taxonomy
This species is remarkably homogeneous, with no subspecies, and according to one study, no genetic variation at the 23 loci tested (Davis 2001, citing Marten and Johnson 1986).
[edit] Etymology
This bird's name commemorates the American ornithologist George Newbold Lawrence.
[edit] References
- BirdLife International (2004). Carduelis lawrencei. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 12 May 2006. Database entry includes justification for why this species is of least concern
- Davis, Jeff N. (June 2001). "A Closer Look: Lawrence's Goldfinch". Birding 33 (3): 212–221.
- Lawrence's Goldfinch - Carduelis lawrencei - Chardonneret gris. Oiseaux.net. Ecopains d'abord (1996-2007). Retrieved on 2007-03-25.
- Sibley, David Allen (2000). The Sibley Guide to Birds. Alfred Knopf, p. 534. ISBN 0-679-45122-6.
[edit] Further reading
[edit] Book
Davis, J. N. 1999. Lawrence’s Goldfinch (Carduelis lawrencei). In The Birds of North America, No. 480 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.
[edit] Articles
- Coutlee E. L. (1968a). Comparative breeding behavior of Lesser and Lawrence’s goldfinches. Condor 70 228–242.
- Coutlee E. L. (1968b). Maintenance behavior of Lesser and Lawrence’s goldfinches. Condor 70 p. 378–384.
- Karubian J & Swaddle JP. (2001). Selection on females can create 'larger males'. Proceedings of the Royal Society Biological Sciences Series B 268, no 1468. p. 725-728.
- Kaufman K. (1993). Notes on goldfinch identification. American Birds 47, no 1. p. 159-162.
- Marten, J. A.; Johnson, N. K. (1986). "Genetic relationships of North American cardueline finches". Condor 88: 409–420.
- Willoughby EJ, Murphy M & Gorton HL. (2002). Molt, plumage abrasion, and color change in Lawrence's Goldfinch. Wilson Bulletin 114, no 3. p. 380-392.
- Zamora J, Ernesto L, Ruiz-del-Valle V, Moscoso J, Serrano-Vela JI, Rivero-de-Aguilar J & Arnaiz-Villena A. (2006). Rhodopechys obsoleta (desert finch): a pale ancestor of greenfinches (Carduelis spp.) according to molecular phylogeny. Journal of Ornithology 147, no 3. p. 448-456.
