ANCHORAGE, Alaska - Opponents of Alaska's predator control program argued Thursday before the Alaska Supreme Court that the program violates the state constitution.

The hearing was another effort by opponents to stop the program in which more than 1,000 wolves and hundreds of bears have been killed to boost moose and caribou numbers since it began in 2003.

Michael Frank, a lawyer for Defenders of Wildlife and the Alaska Wildlife Alliance, told a three-judge panel that the program is not what the state constitution delegates had in mind when they determined Alaska's resources should be managed on a "sustained yield principle."

When they included that in the state constitution, they did not discriminate between prey and predators, and neither should the state, Frank said.

Frank said a review of Board of Game discussions on predator control had no mention of managing wolves and bears for sustainable yield, for making sure numbers don't fall below recoverable levels.

The question boils down to whether predator control can be conducted without regard to sustainable yield of prey animals, namely wolves and bears, Frank said.

"The answer to that is no," he told the judges.

He also maintained that the predator control program is not being operated on a sustained yield principle when 80 percent of wolves and 60 percent of bears are being removed from large areas of Alaska.

Assistant Attorney General Kevin Saxby said there has always been an understanding within state law that some animals are preferred over others. He said if the sustained yield principle was applied as an absolute, then programs such as rat eradication and pike removal would be in jeopardy.

Saxby also asserted that sustained yield is covered in the predator control program in discussions about seasons, bag limits and maintaining minimum population numbers.

Judge Morgan Christen questioned that assertion, saying "It does seem sort of conspicuous that the words are missing."

The state's predator control program began in the McGrath area to respond to complaints there that predators were killing too many moose and caribou calves, leaving them with too animals to hunt for food. The program, which has the strong support of Gov. Sean Parnell, has been expanded to six areas of Alaska.

Under the program, residents are permitted to shoot wolves from the air or conduct land-and-shoot hunting of wolves. The program has expanded to include the baiting and shooting of bears in some areas.

It was not immediately known when the court would issue a decision, but rulings often take months.