Brady Pincushion Cactus

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Brady Pincushion Cactus

Pediocactus bradyi

Status	Endangered
Listed	October 26, 1979
Family	Cactaceae (Cactus)
Description	Dwarf cactus with a single, semi-spherical stem and a straw-yellow flower.
Habitat	Navajoan Desert; shale-derived soil.
Threats	Collectors, off-road vehicles, mineral exploration.
Range	Arizona

Description

Brady pincushion cactus, Pediocactus bradyi, is a dwarf, semi-spherical cactus, typically with a single stem, up to 2.4 in (6 cm) tall and 2 in (5 cm) in diameter. Spines are white or tan and about 0.24 in (6 mm) long. Large straw-yellow flowers bloom in the spring. The green, top-shaped fruit turns brown at maturity. During the dry season, the plants largely retract into the soil.

Two close relatives of the Brady pincushion, Peebles Navajo cactus (Pediocactus peeblesianus ) and Siler pincushion cactus (P. sileri ), are federally listed as Endangered.

Habitat

Brady pincushion cactus occurs in the Navajoan Desert plant community on the Colorado Plateau.It grows where stony rubble overlays soils derived from Moenkopi shale. Ground cover is characterized by scattered, low-growing shrubs, clumps of perennial grasses and seasonal annuals, dominated by shadscale, snakeweed, Mormon tea, and desert trumpet. Habitat elevation is between 3,860 and 4,490 ft (1,176 and 1,368 m).

Distribution

Brady pincushion cactus is a native of the Colorado Plateau north of the Kaibab Plateau. The range extends along the Grand Canyon to the Arizona-Utah boundary. It has been found in Coconino County, Arizona, in an area of about 27 sq mi (70 sq km). The Glen Canyon Dam, completed in 1963, inundated a large area of habitat. Potential habitat in the Marble Canyon area is estimated to be 17,000 acres (6,880 hectares), but only about 20% of this area supports the cactus.

Brady pincushion cactus has been found on both sides of the Colorado River in the area of U.S. Highway 89 near Marble Canyon in northern Coconino County. One population occurs in Glen Canyon National Recreation Area, while other sites are scattered along the river south and west. Many plants are found on Bureau of Land Management (BLM) lands that have been leased for grazing or uranium exploration. The Navajo Indian Reservation east of Marble Canyon supports several groups of plants that fall under the jurisdiction of the Bureau of Indian Affairs. Sites that fall within the Grand Canyon National Park are fully protected by the Park Service.

The total population in 1984 was estimated at about 10,000 plants in a highly localized distribution pattern. The decline in numbers since its discovery in 1958 has been precipitous.

Threats

Brady pincushion cactus is in worldwide demand by collectors of rare cacti. Collectors have decimated populations, particularly where plants are accessible from highways. Even casual collectors seem to easily locate and remove flowering cacti before they can set seed.

Uranium exploration and mining pose a potential threat because much of the habitat lies above a rich, ore-bearing seam. So long as the uranium market remains weak, however, there will be little incentive for mining companies to develop these ores. West of Marble Canyon, off-road vehicle traffic— partly recreational and partly associated with mineral exploration—have torn up large areas of natural vegetation, including several populations of Brady pincushion cactus.

Conservation and Recovery

The U.S. Fish and Wildlife Service and BLM are annually monitoring the size and vigor of the cactus population. Plans for recovery are focusing on developing techniques to propagate the cactus for commercial sale, thereby reducing incentives for collecting wild plants. A greenhouse population would also provide stock for transplanting cacti to other sites within the historic range.

The Plant Resources Institute in Salt Lake City, Utah, has developed a way to propagate several species of Pediocactus by transplanting cultivated buds; funding availability will determine the extent to which this program will include the Brady pincushion cactus.