WASHINGTON (CN) - With fewer than 150 blue-throated macaws left in the wild, the U.S. Fish and Wildlife Service has proposed the Bolivian bird for endangered listing status under the Endangered Species Act, according to an agency rule.
The USFWS was first petitioned on behalf of the bird in 1991, and found that listing was warranted in 1994. The agency was prevented from pursuing the listing due to other listing priorities. The bird was given a listing priority number (LPN) of 2. "An LPN of 2 reflects threats that are both imminent and high in magnitude," the rule said. Even though the agency has reviewed the birds' status each subsequent year, the listing finding remained "warranted but precluded" through 2011.
Collection and the pet trade have had serious effects on the birds in the past. Pre-Columbian art features the birds' feathers in headdresses. There is evidence that the birds have been household pets since A.D. 1000 and were traded over a wide area. "The most significant impact to the decline of this species' population was likely due to collection for museums during the late 1800s and early 1900s," the rule said. "During this time period, bird-skin traders of European descent sold thousands of bird skins, especially to museums in the United States for at least three generations."
Bolivian law has banned export of the birds since 1984, but poaching for local sale continues, the rule said.
The population has declined to less than 150 individuals and "it is likely the population is nearer to 115 individuals," the agency said. The birds' habitat has steadily declined over thousands of years and they are now restricted to small "islands" of habitat within privately-owned cattle pastures in Bolivia. These islands are on higher terrain "primarily formed as mounds resulting from prehistoric human existence in this region," according the agency. The mounds, most raised less than one meter, are surrounded by low areas that regularly flood. It is believed that historic human culture manipulated the water flow to create the drier plains. Several species of palms grow on the mounds, including the macaws' favorite motacú palm, used for nesting and for food. The palm forests have been largely converted to pasture for cattle grazing since World War II, when cattle were first introduced to Bolivia.
Despite conservation efforts, the birds are further challenged by predation from other birds, parasites, severe weather and competition with other species. Many nestlings die because the parents cannot find enough to eat. Weaker nestlings are allowed to die so the stronger ones might live. Sometimes the dead palms preferred for nest sites collapse, especially in severe storms. "However, researchers are working with this species to introduce nest sites that are safer and less prone to predation and nest failure due to extreme weather events," the rule noted. "The effect of the death of each new nestling on the population of blue-throated macaws is devastating to the viability of the population."
The agency seeks comments and information on the proposed listing through March 11 and any public hearings requests by Feb. 25.
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