Attwater's Greater Prairie Chicken

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Attwater's Greater Prairie Chicken

Tympanuchus cupido attwateri

StatusEndangered
ListedMarch 11, 1967
FamilyPhasianidae
DescriptionHenlike bird, heavily barred with dark brown and buff; male has orange eye combs and neck skin.
HabitatCoastal Prairie
FoodPlants, insects.
ReproductionAverage clutch of 12 eggs.
ThreatsAgricultural and residential development.
RangeTexas

Description

Attwater's greater prairie chicken is a medium-sized grouse about 17 in (40.8 cm) long, with a barred, brown and buff pattern. It has a short, rounded, dark tail (black in males, brownish in females). Males have orange combs over the eyes, and an area of orange skin on either side of the neck, which is inflated during courtship display.

Behavior

Prairie chickens feed on plants and insects. The bulk of their diet consists of the green foliage and seeds of wild plants. Insects are a seasonal part of their diet. In early spring in preparation for breeding, the male struts and erects his neck feathers to reveal an orange, inflated patch of skin. Breeding grounds are called "booming grounds" from the bird's low booming call. These grounds can be natural grassy flats or artificially maintained surfaces, such as roads, airport runways, or oil well pads. Nesting sites are usually located in tall grasses. Females lay an average clutch of 12 eggs during April; incubation is about 24 days. Young birds fledge in seven to 10 days and are tended by the female.

Habitat

Attwater's greater prairie chicken inhabits coastal prairie. Most of the habitat is dominated by tall dropseed, little bluestem, sumpweed, broom-weed, ragweed, and big bluestem. Prairie chickens use shorter grasses for courtship and feeding; tall grasses for nesting, loafing, and feeding.

Moderate cattle grazing can actually be beneficial to prairie chicken habitat. Grazing or, in its absence, prescribed burning maintains greater species diversity within grassland communities and helps prevent invasion of woody plants, such as Maccartney rose and eastern baccharis.

Distribution

Attwater's greater prairie chicken once ranged in a narrow strip, 30 mi (48 km) wide, that extended along the coast from the southern tip of Texas to mid-Louisiana. In the 1800s there were probably one million prairie chickens, but by 1940 the population had declined to about 8,700 individuals.

At present, the prairie chicken is restricted to a very narrow band along the Texas coast, some offshore islands, and remnant inland populations. More than 40% of the present population lives in a contiguous area in Aransas, Goliad, and Refugio counties, Texas. A population has also been established at the Tatton Unit of the Aransas National Wildlife Refuge.

In Goliad County, the population peaked in 1974 at 486 birds, and by 1982 had declined to 62 birds. Land-use patterns have remained consistent during this period and the reason for this decline is unknown. The 1980 estimate for Refugio County was 726 chickens, but by 1982 was down to 438. Only 20 chickens were estimated for Aransas Country in 1982. Relatively large numbers also occur in Austin and Colorado counties, which had populations of 250 and 200, respectively, in 1982. The population of Attwater's greater prairie chicken has continued to decline. A 1982 census counted 1,282 birds, but by 1988 the total population was estimated at only 926 birds.

By 1994, only about 158 birds survived in the wild and a mere 2% of its original habitat remained, primarily in four Texas counties. Considered one of the most endangered species in the United States, Attwater's greater prairie chicken has been under protection of the U.S. Fish and Wildlife Service (FWS) since 1973. In 1992, the Fossil Rim Wildlife Center and Texas A&M University joined efforts with the FWS and others to save this bird from the brink of extinction through captive breeding and habitat protection.

Threats

The dramatic decline of Attwater's greater prairie chicken over the past century is typically ascribed to two main forces: over-hunting and habitat loss due to over-grazing and industrial expansion. In the early 1900s, the prolific prairie chicken quickly became an important food source for southern settlers. The breeding habits of this grouse also made it a prime target for those interested in sport hunting. Each spring, prairie chickens gather to breed on "leks" or "booming grounds." Males congregate on these exposed short grass or bare flats of land to attract females by strutting, calling and displaying their stunning plumage. The approach of hunters would rarely be noticed by these birds so engrossed in their courtship activity. It was common for hunting parties to exterminate entire flocks of prairie chickens on the booming grounds and leave hundreds behind rotting in the sun. Fueled by the traditional incentive that whoever shot the fewest birds had to pay for the trip, one hunting camp reported more than 1,000 birds left behind.

Compounding the effects of over-hunting, over-grazing by cattle led to alteration of the taller-grass habitats essential for nesting and roosting. Meanwhile, urban and industrial expansion caused habitat fragmentation, and newer, intensive agriculture practices destroyed important buffer zones and sources of food for the birds. Only a precariously low population of the once abundant Attwater's greater prairie chicken survives. Its future is largely in the hands of those dedicated to protecting it through a program of habitat protection, captive breeding and reintroduction.

Conservation and Recovery

In the 1960s, the World Wildlife Fund-U.S. purchased habitat for the prairie chicken in Colorado County, Texas. This step was closely followed by a private donation to the FWS to provide chicken habitat adjoining Aransas National Wildlife Refuge. This land became the Attwater's Prairie Chicken National Wildlife Refuge when it was transferred to FWS control in 1972. Additional land acquisition has added several thousand acres to the refuge.

Even though refuge areas have been established, habitat loss continues, and the outlook for Attwater's greater prairie chicken is not bright. If it is going to survive, larger blocks of native prairie must be preserved. Biologists predict that chicken populations in Galveston, Harris, and Brazoria counties will disappear because of continued urbanization. In 1988 biologists recommended establishing a captive propagation program to restock wild populations.

In 1992, the FWS selected Fossil Rim Wildlife Center to begin the captive breeding portion of the Attwater's Prairie Chicken Recovery Program. Fossil Rim had previously undertaken an earlier pilot study on the captive breeding of greater prairie chickens, a close cousin of Attwater's. In 1994, Fossil Rim was joined in this cooperative program by both the Houston Zoological Gardens and Texas A&M University. The goal of the Recovery Program is to restore and maintain a genetically viable, self-sustaining population of at least 5,000 individuals in three different areas of Texas.

Each spring, members of the recovery team collect eggs from wild nests to be incubated and hatched in captivity. This process begins early in the breeding season so that wild hens will renest and their reproductive efforts will not be greatly reduced. Young produced in captivity may then be used either for future reintroduction to the wild or to bolster the captive flock. In 1994, the first captive bred young were hatched at Fossil Rim Wildlife Center from adult birds that originated from eggs collected from the wild in 1992. So far, only Fossil Rim has bred Attwater's greater prairie chickens in captivity, but this is likely to change as program participants continue to build the captive flock and refine their knowledge of the species.

In 1994, 42 Attwater's greater prairie chickens were in captivity, including 23 males and 19 females. Each year eggs are collected from wild nests to enhance the genetic variation in the captive population. Habitat protection continues through FWS management of the Attwater's Prairie Chicken National Wildlife Refuge, containing 8,000 acres (3,237.6 hectares) of Texas coastal tall grass prairie. If necessary, surplus captive hatched young will be made available for reintroduction to the Attwater's Prairie Chicken Wildlife Refuge. Although its future remains uncertain, all are optimistic that this unique prairie grouse will once again strut in healthy numbers on Texas booming grounds.

Contacts

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
P. O. Box 1306
Albuquerque, New Mexico 87103-1306
Telephone: (505) 248-6911
Fax: (505) 248-6915
http://southwest.fws.gov/

Fossil Rim Wildlife Center
P. O. Box 2189
Glen Rose, Texas 76043-2189.

References

Bowdoin, Julia M. 1999. "Texans Flock to Save a Native Grouse: The Attwater's Prairie Chicken Recovery Plan." AZA Conservation Spotlights.

U.S. Fish and Wildlife Service. 1983. "Attwater's Prairie Chicken Recovery Plan." U.S. Fish and Wildlife Service, Albuquerque.