LOWER GRANITE DAM (AP) - Mike Peterson saw something he had never seen before at Lower Granite Dam's fish window.

Then he saw another, and another. By the time a half-hour had gone by on Tuesday about 10 sockeye salmon, the most endangered salmon species in the Columbia River basin, swam past the window.

"I would never have thought I could be here and see a sockeye come through the window. There is another one," he said. "These things are pounding through right now."

Peterson, a fisheries biologist for the Idaho Department of Fish and Game, has spent a lot of time looking at fish here. When he was in graduate school at the University of Idaho he used to visit the ladder every few weeks to watch steelhead and chinook salmon. He would sit for hours mesmerized by the fish.

He even visited in July hoping to see a sockeye.

But sockeye were the rarest of fish then, on the brink of extinction. Some years only a handful made it as far as the dam, the last one on the Snake River that salmon and steelhead must pass on their drive for spawning grounds. Only a few years ago, seeing a sockeye at the dam would have been akin to drawing a royal flush when playing five-card stud poker.

Now Peterson sees sockeye all the time. He works on a sockeye conservation project where the returning fish are trapped in the Stanley Basin and bred in a hatchery.

That program has dramatically increased the number of sockeye smolts raised and released each year. The releases, which rose from about 30,000 to 200,000 annually, have led to an uptick in the number of adults that make it back to Idaho's Stanley Basin each year.

Last year more than 1,200 were counted at the dam and more than 800 returned to their spawning grounds. This year as many as 1,500 might make it at least as far as Granite and perhaps 1,000 to Stanley Basin.

Peterson was at the dam to work on a new sockeye conservation strategy. Although sockeye have taken a step back from the brink, they remain critically endangered. They also return in the middle of summer when high water temperatures in the Snake and Salmon rivers can be lethal to salmon and steelhead.

Fisheries biologists fear high river temperatures, combined with a low number of returning sockeye in some future year could spell disaster and set back the conservation efforts.

So this year they are trapping a handful of the fish that pass the dam each week and trucking them to Eagle Fish Hatchery for safe keeping.

"This is to develop the technology and protocols (so) if we ever have conditions where we only expect 100 fish to Lower Granite, we can go collect those fish," he said.

During salmon and steelhead runs, a small portion of the returning fish are trapped at the dam. Currently Darren Ogden, a fisheries biologist with the National Oceanic and Atmospheric Administration, is trapping about 4 percent of the run. That means a trap on the fish ladder is open about 4 percent of every hour.

Every other day, Peterson and fish and game biologist Dan Green visit the dam to see if any sockeye are in the trap. On Tuesday there were.

"We got four, which is the best day so far," Peterson said.

Those four sockeye were loaded into tanks in the back of a pickup truck and whisked to the hatchery where they will be kept for a few months. In the early fall they will be spawned and their offspring will be released back into Redfish Lake or one of its sister lakes, Alturas and Pettit.

It's all part of an effort to make sure sockeye don't become extinct. Idaho hopes to build a new hatchery near American Falls devoted strictly to sockeye. When that happens, about 1 million sockeye smolts will be raised and released each year. Peterson said that could lead to returns of 5,000 to 10,000 adults each year.

On Monday, 142 sockeye were counted passing the dam. That is a record and it could be short lived. Peterson expects daily counts to be around 100 or above for a short period.

"It's a good feeling. Things are going well," Peterson said of the state of the sockeye run.

Biologists are learning that sockeye can succeed if they survive their outmigration to the ocean as juveniles.

"If we can get them to the ocean it appears right now they are going to come back," he said.

Unlike steelhead and chinook, Peterson said sockeye smolts tend to migrate quickly downriver and in one big group.

That safety-in-numbers strategy might help them survive better. It takes juveniles about nine to 12 days to make it from Stanley to Lower Granite. Chinook take 25 to 30 days. The adults are also quick. Peterson said it takes adults about one month to travel from Granite, more than 400 miles upriver to Stanley.