Physical characteristics: Red crossbills show much geographic variation in body size, and in bill size and shape, but not in color. They have a fairly heavy body (about the size of sparrows), a short forked tail, and a stout bill where the tips of the upper and lower mandibles (parts of bill) cross over. Males are colored an overall dusky brick red with dusky wings that have reddish edging, and a dusky black tail that is short and notched. The undertail coverts are dark with whitish edging, while the belly is whitish gray. Females are gray tinged with dull green, brightest on rump, with darker (dusky black) wings. Juveniles have weakly crossed mandibles, gray-olive upper-parts, whitish under parts that are streaked with dark brown and washed with yellow, and a buff-yellow rump. Adults are 5.3 to 6.5 inches (14.0 to 16.5 centimeters) long and weigh about 1.4 ounces (40 grams). Their wingspan is 10.0 to 10.8 inches (25.4 to 27.4 centimeters) long.
Geographic range: Red crossbills range through the boreal and montane forest regions of both North America and Eurasia. They are found from coast to coast on both continents, breeding from southern Alaska, Manitoba, Quebec, and Newfoundland, south in west to northern Nicaragua, in eastern United States to Wisconsin and North Carolina.
Habitat: Red crossbills are mostly found in pine-containing conifer forests.
Diet: Their diet consists of conifer seeds mostly from the tree but sometimes off the ground, especially liking pine seeds. They remove seeds with its crossed bills and flexible tongue. The birds also eat insects and caterpillars.
Behavior and reproduction: Red crossbills are very social birds, especially during their nonbreeding season when they are found in large flocks. They sing a series of two-note phrases followed by a trilled warble, such as "jitt, jitt, jitt, jiiaa-jiia-jiiaaaa," "chipa-chipa-chipa," and "kip-kip-kip." The birds defend their territory with a repeated series of simple chirps as they fly around. During courtship, males fly above a female while vibrating wings and singing. Breeding pairs are monogamous. Females build saucer-shaped nests of twigs, grass, bark strips, and rootlets. Nests are lined with finer grasses, fur, feathers, hair, and moss, located near the end of conifer branches, and 6.6 to 40.0 feet (2 to 12 meters) off the ground. Females lay three to four light green-blue eggs that are spotted with brown and lilac. The incubation period is twelve to eighteen days. Only females incubate. The helpless newborns are brooded by the female and fed by both parents. The fledgling period is fifteen to twenty days. One to two broods occur each year.
Red crossbills and people: There is no known significant relationship between people and red crossbills.
Conservation status: Red crossbills are not threatened. They are abundant throughout their range, but some species are declining in numbers due to human activities such as logging operations. ■
FOR MORE INFORMATION Books:
Alsop, Fred J. III. Birds of North America. New York: Dorling Kindersley, 2001.
Baughman, Mel M., ed. Reference Atlas to the Birds of North America. Washington, DC: National Geographic, 2003.
del Hoyo, Josep, Andrew Elliott, Jordi Sargatal, Jose Cabot, et al., eds. Handbook of the Birds of the World. Barcelona: Lynx Edicions, 1992.
Dickinson, Edward C., ed. The Howard and Moore Complete Checklist of the Birds of the World, 3rd ed. Princeton, NJ and Oxford, U.K.: Princeton University Press, 2003.
Field Guide to the Birds of North America, 4th ed. Washington, DC: National Geographic Society, 2002.
Forshaw, Joseph, ed. Encyclopedia of Birds, 2nd ed. San Diego, CA: Academic Press, 1998.
Harrison, Colin James Oliver. Birds of the World. London and New York: Dorling Kindersley, 1993.
Kaufman, Kenn, with collaboration of Rick and Nora Bowers and Lynn Hassler Kaufman. Birds of North America. New York: Houghton Mifflin, 2000.
Sibley, David. The Sibley Guide to Birds. New York: Alfred A. Knopf, 2000.
Terres, John K. The Audubon Society Encyclopedia of North American Birds. New York: Knopf, 1980.
Adkisson, Curtis S. "Red Crossbill." The Birds of North America, No. 256, 1996 (Cornell University). http://birds.cornell.edu/birdsofna/excerpts/ crossbill.html.
HAWAIIAN HONEYCREEPERS Drepanididae
Class: Aves Order: Passeriformes Family: Drepanididae Number of species: 51 species
phylum class subclass order monotypic order suborder family
Hawaiian honeycreepers are a group of birds with very unique appearances. The Drepanididae family is divided into three groups: Hawaiian finches, seed-eaters with thick finchlike bills and songs similar to the cardueline finches; Hawaiian creepers and relatives, including nukupuu, generally green-plumaged (feathered) birds with thin bills that feed on nectar and insects; and mamos, iiwis, and relatives, red plumaged birds that feed on nectar and sing songs of squeaks and whistles.
Hawaiian honeycreepers are small- to medium-sized birds that are often mistaken for finches. They have a compact body and a relatively straight to greatly curved bill, with the wide variation of bill sizes and shapes due to the type of food eaten (some have finch-like bills adapted to feeding on seed pods, while many others have pointed or curved bills in order to forage (search for food) for insects and nectar). They have nine large primary feathers on each wing (with a tenth primary feather that no longer functions and has mostly disappeared), and a tube-like tongue (in most species) with a fringed tip that is adapted to nectar feeding. Plumage comes in a wide variety of colors from dull olive green to brilliant yellow, crimson, and multi-colors. Male Hawaiian honeycreepers are often more brightly colored than females.
Hawaiian honeycreepers are found only on the Hawaiian Islands. They are believed to have descended from a single species of cardueline finch that came to the Hawaiian Islands (it is believed) about three to four million years ago.
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