Hedge Sparrows: Prunellidae

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HEDGE SPARROWS: Prunellidae

DUNNOCK (Prunella modularis): SPECIES ACCOUNT

PHYSICAL CHARACTERISTICS

These birds, also known as "accentors," are small and sparrow-like in appearance but not related to sparrows. The bill of a hedge sparrow is slender and more pointed than the sparrow. They range in size from 5 to 7 inches (13 to 18 centimeters), with a weight of 0.5 to 1.4 ounces (18 to 40 grams). The differences between the male and female are slight, though the male has longer wings, with ten functional primary feathers that can be rounded or pointed at the tip. The male is heavier than the female. The legs and feet of the bird are very strong. In general, the anatomy of the birds is strong and muscular, a feature that has been adapted due to their diet.

In color, a hedge sparrow tends to be brown-toned gray or a rusty brown. Males are slightly brighter than females, but are otherwise similar in appearance.


GEOGRAPHIC RANGE

Hedge sparrows are known to be widely distributed throughout the Palearctic region that includes the area from western Europe to Japan, in Asia north of the Himalayan mountains, and in Africa, north of the Sahara desert.


HABITAT

Hedge sparrows tend to live in the thick undergrowth of shrubs, and in alpine meadows rather than in the trees themselves. Habitats can vary slightly among the species.

The robin accentor can be found at high altitudes in central Asia, and prefers to live in dwarf rhododendrons and other scrub, or among the willows of damp meadows.


DIET

Accentors gather food by hunting or foraging on the ground, preferring invertebrates that crawl, particularly insects such as beetles, flies, aphids, ants, spiders, and worms. They feed primarily on seeds and berries in the winter and forage together in flocks.


BEHAVIOR AND REPRODUCTION

Accentors tend to have a very developed social system even though they are also known to be quiet and unobtrusive. Most of their activity occurs on the ground, or close to it, moving through running and hopping with small flicks of the wings and tail. When they are in flight, they exhibit rapid and undulating moves.

Female accentors tend to be exclusive. The male of some species, such as the dunnock, might set up song territories in order to compete for and monopolize females. The result can be a male with two or three females, called polygyny (puh-LIH-juh-nee), or it can be a female with two or three males, called polyandry (PAH-lee-an-dree); or several males associated with several females, known as polygamy (puh-LIH-guh-mee). Polyandry is considered to be unusual even though it does occur. In such a situation, the breeding territory would be larger than for a single male-female pairing, providing for more protection against a greater number of predators. The Himalayan accentor can breed at altitudes as high as 16,400 feet (5,000 meters) into the mountains.

SIDETRACKED TO NORTH AMERICA

The Siberian accentor has a habit of straying over to northwestern America on occasion, but primarily on the Aleutian Islands and western Alaska. This has been witnessed in the months of October through January. The subarctic forests of Siberia are the bird's usual breeding grounds.

Breeding season for accentors runs from late March to August, with variations among the species depending on location and latitude. They lay a clutch of three to six eggs that are light blue-green to blue. Two clutches are generally bred and hatched every year, with an incubation period of eleven to fifteen days, with the nestlings raised another twelve to fourteen days before they leave the nest, or become fledglings. Both male and female take care of the young together.

HEDGE SPARROWS AND PEOPLE

Accentors have an impact on people primarily in regard to ecotourism and the economic benefits from visitors focused on following birds in their natural habitats.


CONSERVATION STATUS

The Yemen accentor has been listed as Near Threatened, in danger of becoming threatened with extinction. Due to grazing animals, in addition to human behavior, the shrubland habitat on which the bird relies has been degraded. Other species have also declined but are not considered at risk. During the 1980s, the dunnocks that breed in England declined, but are maintaining themselves against further loss into the twenty-first century.

DUNNOCK (Prunella modularis): SPECIES ACCOUNT

Physical characteristics: The dunnock is a relatively small bird that has an average length of 6 inches (15 centimeters), and weighs about 0.7 ounces (19 grams). Like other accentors, its beak is pointed and slender and its feet and legs are sturdy. The dunnock can have a blue-gray head and breast, and a light and dark brown back with streaks, brown-streaked flanks, and pink legs. The under parts of the dunnock tend to be uniformly gray with apricot markings.


Geographic range: The dunnock can be found throughout Europe, as far east as the western regions of Russia. In the northern regions, the dunnock is migratory. Those living in the southern parts of France and Spain tend to reside there on a continual basis. Between 1860 and 1880, the dunnock was introduced to New Zealand and remains there, as well.


Habitat: The dunnock resides in woods that have an ample amount of undergrowth, as well as in the hedges and shrubbery at the edges of forests. They also thrive in farm areas that have a lot of vegetation, and in the gardens of the United Kingdom and New Zealand.


Diet: Dunnocks are omnivores, eating various invertebrates such as insects, spiders, and worms during warm months. In the winter they survive on seeds and berries, some of the various kind of seeds are in feeders meant for songbirds in gardens and backyards.


Behavior and reproduction: Dunnocks are known for their secretive behavior and tend to be shy in their habits. Most of the populations are migratory. During breeding season, they are seen either as individuals or in pairs. During the winter they tend to gather in large flocks in order to forage for food—with a good food source, a hundred or more might gather. The bird's voice is heard in a short but complex song that is composed of a succession of rapid and even notes and trills.

Breeding season for dunnocks runs approximately from the beginning of April to the end of July, generally raising two broods a year. The incubation period lasts from twelve to fourteen days, and the young are ready to fly about eleven to thirteen days after they are hatched. Both male and female parents care for the young. Dunnocks are sometimes polyandrous breeders, with a female mating with several males within the breeding territory. In that case, it is usual for all of the parties involved to raise the young.

Dunnocks and people: Dunnocks provide an economic benefit due to the numbers of people who engage in bird watching and the travel that sometimes accompanies it. The dunnock is also well known in the English countryside. In 2001, the ticks that live on dunnocks and other migratory birds were linked to the spread of a bacterial pathogen known as Ehrlichia phagocytophila, which causes the rare human disease of ehrlichiosis. This disease has been compared to Rocky Mountain spotted fever and emerges about twelve days following the bite of a tick. Though cases have occurred in the United States, the illness tends to be centered in the Far East and Southeast Asia, with most cases reported in western Japan.


Conservation status: The dunnock is not a threatened species, although its population in Britain did experience a decline by 45 to 60 percent between 1975 and 2001. Since 1986 the population remained steady. The cause was unknown. The decline was not experienced throughout the British Isles and Wales actually enjoyed a population increase. ∎


FOR MORE INFORMATION

Books:

Alsop, Fred J. III. Birds of North America. Smithsonian Books. London and New York: Dorling Kindersley Publishing, 2001.

Campbell, Bruce, and Elizabeth Lack, eds. A Dictionary of Birds. Vermillion, SD: Buteo Books, 1985.

Elphick, Chris, John B. Dunning Jr., and David Allen Sibley, eds. The Sibley Guide to Bird Life & Behavior. New York: Alfred A. Knopf, Inc., 2001.

Fisher, James, and Roger Tory Peterson. The World of Birds. Garden City, NJ: Doubleday & Company, Inc., 1964.


Web sites:

"Dunnock." Bird Diary. http://www.birddiary.co.uk (accessed on May 5, 2004).

"Dunnock." British Garden Birds. http://www.garden7ndash;birds.co.uk/dunnock.htm (accessed on May 5, 2004).

"Breeding Birds in the Wider Countryside." Joint Nature Conservation Committee. http://www.bto.org/birdtrends/wcrdunno.htm (accessed on May 5, 2004).

"Dunnock." New Zealand Birds. http://www.nzbirds.com/Dunnock.html (accessed on May 5, 2004).

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Hedge Sparrows: Prunellidae

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