With Diamond Lake trapped beneath a heavy layer of ice and snow, anglers should expect to add an ice auger to their equipment list for what could be the last trout opener at the lake.

With Diamond Lake trapped beneath a heavy layer of ice and snow, anglers should expect to add an ice auger to their equipment list for what could be the last trout opener at the lake.

State fish biologists are backing a proposal for the first time in decades to open Diamond Lake to year-round fishing beginning in 2013, a move they say makes as much sense socially as it does biologically.

Mining even more stocked rainbow trout will help trout growth rates, zooplankton levels, water clarity and overall lake health, which has been guarded so closely since the 2006 poisoning of the lake to kill off invasive tui chub.

"I think we're doing a good job at that already," says Laura Jackson, Umpqua District fish biologist for the Oregon Department of Fish and Wildlife. "This just provides us with a little bit more of a buffer."

The proposal is one of 133 possible changes to state angling regulations — and one of four proposals offered for Diamond Lake — and this one carries the all-important approval from ODFW biologists.

But that doesn't make it a done deal.

All the proposals are up for public review, and the agency has scheduled a dozen public meetings statewide to gauge public support for them.

A public meeting is planned for 7 p.m. May 10, at the Jackson County Auditorium, 400 Antelope Road, White City.

The proposals, as well as public comments on them, will be reviewed by the Oregon Fish and Wildlife Commission when it meets Aug. 3 in Salem.

Final adoption of the new regulations package is set for the commission's meeting Sept. 7 in Hermiston.

All the regulations adopted at that meeting will go into effect Jan. 1.

Despite opening a new year-round business opportunity for Diamond Lake Resort, the resort's Rick Rockholt is lukewarm to the idea. The resort does not oppose the year-round season, but its managers instead have favored a separate proposal that would open the lake to fishing in March.

Rockholt says he's worried about safety on a lake where the ice and snow layers aren't as strong as frozen lakes in the Midwest.

"We're concerned about people ice fishing in the winter. We're even concerned about people ice-fishing next week," Rockholt says.

"They'll watch the Outdoor Channel and think they can drive out there," he says. "During the first two weeks of the season last year, people were driving four-wheelers out on the ice. It's crazy."

ODFW permits year-round fishing at other lakes, including nearby Lake of the Woods and Fish Lake, Jackson says. And just like at those other lakes, anglers will have to use good judgment, she said.

"It doesn't matter if you live in Oregon, Wisconsin or Michigan, you have to use good safety consciousness," Jackson says.

Diamond Lake has been a fishing aberration since nearly 100 million tui chub were killed off because their presence ruined the trout fishery and altered the lake's ecology and water quality.

The lake has been restocked annually with trout, creating the Northwest's best trout lake. The insect-rich lake is a true trout factory, producing fish with football-shaped bodies, but biologists worry that the lake's bulging population could harm the lake's ecology the way tui chub did.

In 2010, anglers fishing under a five-trout daily limit were releasing 37 percent of the fish they caught. So last year ODFW made Diamond Lake the state's only lake with an eight-fish limit, which dropped the release rate to 31 percent, which adds up to about 55,000 fish being released, Jackson says.

That's one of the reasons this year's stocking will be reduced to 166,000 fingerling trout from 200,000 in 2011 and 315,000 in 2010.

Creel surveys have shown that the lake's ice fishers keep more trout than summer anglers, Jackson says. So she estimates that a year-round season would get another 25,000 trout caught and kept next year.

"It could be more, and we can withstand that," she says.

If adopted, some logistics would have to be worked out, such as whether the Forest Service would improve access amid heavy winter snows, Jackson says.

But overall, she says, opening the lake year-round will help keep the lake the trout gem that it is.

"We want to make sure we keep the lake in balance," Jackson says.

Reach reporter Mark Freeman at 541-776-4470 or mfreeman@mailtribune.com.