BOISE (AP) — Idaho wildlife managers are increasing bag limits, expanding trapping opportunities and extending the public hunting season in an attempt to bring down wolf populations across the state.

The Idaho Fish and Game Commission approved the modifications Thursday to the state's 2012 wolf hunting rules. The changes will go into effect when the season opens later this year.

Biologists estimate there are between 500 and 600 wolves roaming the state, down from more than 1,000 when the 2011 season opened last fall.

But wildlife managers say wolves are still negatively impacting big game prized by hunters, specifically elk herds in the northern backcountry.

So far, hunters and trappers have killed 364 wolves since the season opened last fall. Dozens of other wolves have died naturally or killed for attacking livestock.