RENO, Nev. - Conservationists argue in a new report that U.S. taxpayers should stop subsidizing a $100 million program that kills more than 1 million wild animals annually, a program ranchers and farmers have defended for nearly a century as critical to protecting their livestock from predators.

More than 90,000 of the 121,524 carnivores killed in 2007 were coyotes. But the trapping, poisoning and aerial gunning of the predators also is taking an increasing, unintended toll on other creatures, including 511 black bears and 340 endangered gray wolves in 2007, according to a copy of the report obtained by The Associated Press. (AP file) Citing concerns about the economy and the potential for a fresh look at the decades-old controversy in the new Obama administration, 115 environmental groups signed onto a recent letter to Agriculture Secretary Tom Vilsack urging him to abolish the U.S. Agriculture Department's Wildlife Services.

The American Sheep Industry Association, National Cattlemen's Beef Association and more than 70 other livestock production and state agriculture offices in 35 states countered with a letter citing more than $125 million in annual losses to the sheep, goat and cattle industry as a result of predation.

A report by conservationists released Tuesday documents significant increases in recent years in both the number of carnivores killed and the size of the agency's budget - $117 million in 2007, up 14 percent from the average from 2004-06.

"We ask Mr. Obama to get out his scalpel and protect the public's hard-earned dollars from this unscrupulous agency," said Wendy Keefover-Ring, director of carnivore protection for WildEarth Guardians based in Bozeman, Mont.

More than 90,000 of the 121,524 carnivores killed in 2007 were coyotes. But the trapping, poisoning and aerial gunning of the predators also is taking an increasing, unintended toll on other creatures, including 511 black bears and 340 endangered gray wolves in 2007, according to a copy of the report obtained by The Associated Press.

Hundreds of thousands of other animals, including ravens and raccoons, also are killed through the program.

Aides to Vilsack referred questions about the program to USDA's Animal, Plant, Health Inspection Service, which oversees Wildlife Services.

USDA spokeswoman Carol Bannerman said Vilsack intends to review all agency programs but that it would be weeks before he had any idea about possible changes he wants to make.

Bannerman said the federal agency kills predators only when livestock owners or state officials request their assistance. She said most of the time those private individuals or state agencies provide about half the funding for the effort.

"From our perspective, we certainly feel that we have a responsibility to respond to those requests," she said from APHIS headquarters in Riverdale, Md.

Bannerman said the agency is required to review each individual project "and move ahead only if there would be no long-term negative impact on the environment."

"With that mandate ... we can give people an outlet to deal with a problem that if they took into their own hands could have longer-term negative impacts," she said.

The agricultural commodities' groups said in their letter to Vilsack about a month ago that livestock losses to predation cost producers more than $125 million a year.

"Without non-lethal and lethal predator control by Wildlife Services, these numbers could easily double or even triple," said Skye Krebs, an Oregon rancher and president of the Public Lands Council, which spearheaded the letter along with the National Cattlemen's Beef Association.

"The agency provides a means for striking a balance in the wildlife-livestock interface, including limiting the spread of disease from wildlife," Krebs said.