Psittirostra cantans

Physical characteristics: Laysan finches have a large parrot-like (heavy, hooked) bill with the tip of the upper mandible (top part of a bird's bill) forming a tiny downward hook. Adult males have a bright yellow head, throat, and breast, and a gray collar around the neck. They have a grayish brown lower back and rump, and a whitish abdomen. Females are less colorful, with dark streaks in a yellowish crown, a gray collar, a yellowish throat and breast, some streaking on the flanks, and dark brown spots along the back. They are 6.0 to 6.5 inches (15 to 18 centimeters) long.

Geographic range: They are found on Laysan Island in the northwestern Hawaiian Island chain. A small population, which was introduced, exists on Pearl and Hermes Reef (a coral atoll). Both locations are part of a long series of islets northwest of the main Hawaiian Islands.

Habitat: Laysan is a low-lying, sandy island about 1,000 acres (405 hectares) in area that contains no trees but plenty of shrubbery and grasses. Pearl and Hermes Reef is a coral atoll containing several small islands.

Diet: Laysan finches are omnivorous (eating both animals and plants), eating such foods as carrion (decaying animals), various invertebrates (animals without a backbone) such as insects, roots, sprouts, soft parts of plants and seeds, and seabird eggs (including the interiors of tern eggs). With respect to tern eggs, Laysan finches puncture their eggshells with its bill in order to get to the food inside.

Behavior and reproduction: Laysan finches are lively and sociable birds. They are very curious and have no fear of humans, often even letting people to feed them from their hands. Males gather at the start of the breeding season in order to make courting displays toward females. Their song is a complex, canary-like warbling. They make cup-shaped nests from grasses and twigs and place them in clumps of grass or in small bushes.

Laysan finches and people: Wildlife biologists have made strong efforts to preserve the species, and to study the evolution of the species.

Conservation status: Laysan finches are listed as Endangered by the U.S. Fish and Wildlife Service (USFWS) and the State of Hawaii, and as Vulnerable by the World Conservation Union (IUCN). They are often injured or killed by violent storms and the increasing numbers of introduced species of animals that compete with them on their limited habitat. ■

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.

Web sites:

"Hawaiian Honeycreepers: Family Drepanididae." Southwestern Adventist University, Department of Biology, Keene, Texas. http://biology. swau.edu/faculty/petr/ftphotos/hawaii/postcards/birds/ (accessed on July 20, 2004).

WAXBILLS AND GRASSFINCHES Estrildidae

Class: Aves

Order: Passeriformes

Family: Estrildidae

Number of species: 129 species

CHAPTER

phylum class subclass order monotypic order suborder family

PHYSICAL CHARACTERISTICS

Waxbills and grassfinches, commonly called weaverfinches, are relatively small, often brightly colored birds with large, cone-shaped bills. Projections (or swellings) of thick connective tissue, which are located at the edges of the bill and at the gape (width of the open mouth), are one of the weaverfinches most interesting features. The projections are colored a bright white, blue, or yellow, and often edged with black. Their plumage (feathers) often blends in with their environment, but can still be quite colorful. Adults are 3.5 to 6.7 inches (9 to 17 centimeters) long, with a wingspan of about 6 inches (15 centimeters).

GEOGRAPHIC RANGE

They are found in sub-Saharan Africa, southeastern Asia, Australia, and South Pacific islands. Various small populations have been introduced throughout other parts of the world.

HABITAT

Weaverfinches are found in savannas (flat grasslands), forests, and semi-deserts, preferring forest edges.

DIET

Their diet consists of small half-ripe and fully ripe grass seeds, and during the breeding season they also eat arthropods (invertebrate animals with jointed limbs). Ants and termites are eaten at the beginning of the rainy season. They often dash out from a perch to grab an insect and then return to the same perch.

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