ODFW officials and volunteers cruise the Chetco River on Thursday morning. The Pilot/Steve Kadel

John Weber spotted the Chinook salmon carcass on the bottom of the Chetco River and Val Early steered the drift boat that direction.

Weber, an Oregon Department of Fish and Wildlife biologist, pulled the fish up with a hook on the end of a pole and put it in the boat. Then Early, a 30-year river guide, eased the boat to the shore.

Weber jumped out to quickly measure the fish and pull off some scales, putting them into an envelop that will be sent to the ODFW office in Corvallis.

 There, lab personnel will determine the age of the fish and whether it was wild or from a hatchery.

Thursday’s “carcass count” on the river involved 16 people in five boats – ODFW staff members and volunteers from the nonprofit Oregon South Coast Fishermen.

Five or six outings are held during spawning season from early December to mid-January. Statistics are gathered at 11 spots from South Fork to Social Security Bar.

Information gleaned from the work helps ODFW forecast the run size for the following  year and, based on that, set the dates for fishing season. Also, the count of hatchery vs. wild salmon is weighed in making long-term  decisions on the number of hatchery fish to be released.

“It’s a management tool,” Early explained.

Weber said help from the Oregon South Coast Fishermen is important.

“They are dedicated to collecting this data, so if the state doesn’t have the manpower they are willing to make up the difference,” he said.

The Chetco River, designated a wild and scenic river,  was rated No. 7 in 2010 among the most threatened rivers in the country, according to the nonprofit group American Rivers. The threat comes from potential mining operations, the group said.

Thursday, though, the crystal-clear river put on its best show as the boats floated down amid hills shining emerald green in the morning sun. At one spot, two bald eagles ate a salmon carcass on the shore, then took flight as  a boat approached.

Sometimes the carcass hunters find more than 100 fish to catalogue in a single day.

Early said more than 2,000 hours were contributed to the counting project last year by volunteers from the Oregon South Coast Fishermen. The number of salmon returning to the river is increasing in recent years, she added.

“It’s climbing right now although a couple of years ago it was quite low. That was the genesis of this program.”

Her husband, Gary, also a long-time river guide, said the Chetco is one of the most-studied rivers in the state.

He, too, praised the Oregon South Coast Fishermen for their contributions to the resource, including educating children about fishing.

“They are not political and they only have one thing in mind – helping Fish and Game,” Gary Early said.