A First Nations commercial fishing operation on Kamloops Lake is set to proceed in September despite grave concerns about sockeye returns in the Fraser River system.

An official with the program said Friday the native fishery for chinook salmon will be guided by rules from the Department of Fisheries and Oceans. Fishers will also experiment with different ways of netting salmon in order to avoid killing precious sockeye.

The fishery is set to start in the first week of September using an 8.5-metre aluminum fishing boat and an associated 10.5-metre packing boat. While marine boats first trolled the lake in 2010, the Secwepemc Fisheries Commission purchased two vessels this year as part of a long-term commitment to the inland fishery.

"It all depends on the run strength," said Don Ignace, fisheries supervisor for the Skeetchestn Indian Band.

"The method of fishing depends on what we're allowed with bycatch (accidental catching of other species). If we're catching too many sockeye with a gillnet, we'll have to look at other options."

That option may be purse-seining, considered a more difficult alternative for capturing chinook.

Fishers typically use gillnets to hook or entangle salmon. They have some control over what is caught based on the size of mesh.

With purse-seining, nets are circled around and under schools, allowing fishers to close them like a drawstring. Other live species are returned to the lake.

The Department of Fisheries and Oceans said this week it expects a total return of just 2.1 million sockeye on the Fraser River system, meaning a shutdown of the commercial and sport fisheries.

South Thompson Chinook - the target for the Kamloops Lake fishery- are plentiful, by contrast. The goal for the fishery on Kamloops Lake is to catch in the neighbourhood of 5,000 chinook returning to the South Thompson, Shuswap and Little rivers.

While more will be known about returning sockeye in coming weeks, questions remain about how chinook will be targeted. While sockeye tend to school in large numbers, chinook are sporadic and less dense.

"Gillnetting is the preferred method. We use larger mesh to catch the larger chinook," Ignace said. "Sockeye will swim through, but some will get caught."

Efforts are also underway by the fisheries commission to set up an arms-length company, under the Riverfresh Salmon brand. Products are expected to be available locally.