Anticipating that caribou hunters are reaching their quota of 480 animals, state biologists have closed hunting for caribou in the Fortymile herd accessible from the Steese and Taylor highways two days after it opened.

The joint federal-state registration permit hunt of the Interior's largest caribou herd opened Monday and closed Wednesday.

Subsistence hunters can still hunt on federal land in the area.

Fortymile herd harvest management Zones 1 and 3 are closing. Zone 1 includes land accessible from the Steese Highway in state game management units 20B and 25C. Zone 3 is the eastern portion of unit 20E, accessible from the Taylor Highway.

"The caribou are in very accessible locations near both highways," area state management biologist Jeff Gross said in a press release.

Unsuccessful hunters can continue hunting in Zone 2, a huge swath of land north of the Tanana River with the Yukon River near its northern border. Biologists will continue to monitor the hunt to determine if Zone 2 should close before the normal end of the hunt Sept. 20.

The closure affects only state hunting regulations. Federal subsistence hunters can call 1-800-478-1456 for information.

State biologists are trying to grow the Fortymile herd beyond its current size of about 39,000 animals.

Over the winter, a predator control effort had the state shooting wolves from helicopters in an effort to boost caribou numbers. The goal was to shoot 150 wolves, but only about a quarter of that number were taken.

The wolf shooting aims to boost Fortymile caribou numbers to 50,000-100,000 animals.

Regional Fish and Game supervisor David James said in March the state planned to spend about $100,000 on the aerial hunt, hoping to kill 300 of the 400 wolves in area.