The endangered gray wolf wandered 3,000 miles in search of a mate -- only to be illegally poisoned in northwest Colorado in 2009.Now state and federal investigators are asking the public to help identify whoever used a banned poison to kill the 2-year-old female wolf.The wolf, which was radio-collared in a research project, meandered an estimated 3,000 miles across Montana, Wyoming, Idaho, Utah and Colorado according to tracking signals, said Steve Oberholtzer, special agent in charge for the U.S. Fish and Wildlife Services Mountain-Prairie Region. Its carcass was found in Rio Blanco County in April 2009 after researchers received a mortality signal indicating the wolf had stopped moving.Tests showed the wolf died after ingesting the banned poison, Compound 1080, and investigators suspected the poisoning occurred close to where she was found near Rio Blanco County Road 60, the U.S. Fish and Wildlife Service said in a Monday press release."When used improperly, Compound 1080 is an indiscriminate killer of wildlife, and we are asking the public to help us identify who used this banned poison in Colorado," Oberholtzer said.Compound 1080 was once commonly used in the United States to control rodents and livestock predators such as coyotes and foxes. It was banned in the U.S. in 1972, but the rule was modified in 1985 to allow the poison to be used under tight regulation in some states for predator control.Gray wolves in Colorado are federally protected by the Endangered Species Act. The law prohibits anyone from harassing, harming, pursuing, shooting, wounding, killing, trapping, capturing, or attempting to do any of these things, to any endangered species unless specifically authorized by federal regulations to do so, authorities said. While some wolves have been illegally killed by poisoning, it is a rare occurrence compared to illegal shooting, officials said. Penalties for illegally killing an endangered species can range up to a $100,000 fine and a year in jail.State and federal wildlife officers could not find evidence of traps and poison baits in the area around the wolf's carcass, authorities said. Investigators also were unsuccessfully in searching for poisoning evidence along the radio-tracked path the wolf traveled just before it was killed.Several carcasses were found, including multiple old sheep carcasses and one coyote carcass, but no illegal poisoned bait stations were discovered, authorities said.Federal biologists said the animal, which had the research identification 341F, broke from her pack just north of Yellowstone National Park in September 2008 as it began the seven-month journey. Young gray wolves leave their native pack, often traveling long distances in search of a mate and the opportunity to establish a new breeding pack, officials said.Anyone with information about the wolfs death that would be useful to investigators is urged to contact either the Colorado Division of Wildlifes Operation Game Thief hotline number at 877-265-6648 or the U.S. Fish and Wildlife Service at 720-981-2777.