The camera that Alaska Wildlife Troopers say caught a pair of men illegally shooting three black bears to death was part of a study meant to determine black bear numbers in Prince William Sound, state officials said Thursday.

Andrew Renner, 41, and Owen Renner, 18, were charged this week with killing the sow and its two cubs in April, on the sound’s Esther Island. Troopers seized a truck, boat and hunting rifles the Wasilla residents allegedly used to reach the bears, then shoot first the sow and its “screaming” cubs.

Bruce Dale, director of Fish and Game’s Division of Wildlife Conservation, said Thursday that the camera which recorded the April 14 crime had been placed as part of a 2016 effort to study black bears in the Prince William Sound area.

Biologists at Fish and Game, as well as the U.S. Forest Service, have been attempting to make the first detailed count of bears in the area after black bear kills in the area rose sharply starting in the 1990s, tripling by 2007 before falling sharply through 2015. Dale attributed the surge in area bear hunts to the opening of road service to Whittier through the port’s rail tunnel, which was modified to accommodate vehicles in 1998.

“We started adjusting seasons and bag limits as it became more popular, then we saw a decline in harvests,” Dale said.

“We decided to put a camera on it to see the den emergence, watch the bears’ movements and actions and compare that to the collar movements,” Dale said.

Alaska State Troopers spokeswoman Megan Peters said in an email that no region of the state has a particularly large amount of illegal bear kills.

“(S)pring hunts attract the most attention due to lack of vegetation/food sources, and therefore seem to produce the most violations,” Peters wrote. “Sows [with] cubs are usually the bears killed when an illegal take of a bear occurs.”

Although wildlife troopers see many cases of illegal bear kills each year, both deliberate and accidental, “we have very few cases where violators enter dens to kill bears.”

There are a few cases each year, according to Peters, in which “some type of media footage documents someone illegally taking a bear.”

Fish and Game had originally planned to leave the camera in place for the summer, then retrieve it to review its footage alongside the sow’s collar telemetry. Instead, Dale said, “the collar turned up in Palmer and the troopers collected it.”

Nobody at Fish and Game had seen the camera’s footage before it was seized as evidence, Dale said. Prosecutors released some of what the Renners said in 30-second recorded clips from the April 14 killings and a cleanup of the site two days later, including Owen Renner saying, "They'll never be able to link it to us."

Although no concrete numbers have emerged for how many black bears live in the area near the sound, Dale said biologists had made estimates based on prior work in Southeast Alaska and Kenai, as well as other bear surveys in Southcentral and Interior Alaska.

“We have a good range of ideas for habitats across the state, so we have a good idea of what should be there,” Dale said.

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