Tribal and sport fishermen were able to fish for Nisqually winter chum this year thanks to a new in-season management tool developed by the Nisqually Indian Tribe and the Northwest Indian Fisheries Commission.

The tribe built a new predictive model that uses in-season data to update escapement expectations. Pre-season estimates of this year’s winter chum run were too low to allow for harvest.

“Now we can determine the entire run size much earlier than usual,” said David Troutt, natural resources director for the tribe. “We’re able to adjust our fishing plans to reflect what the run looks like in real-time.”

In-season changes to fishing plans usually include a watershed-wide count of salmon on the spawning grounds. On the Nisqually, this escapement number has not been available until weeks after the fishing season closed.

The new model uses data gathered during intense tribal spawning surveys on Yelm Creek. Tribal scientists established a connection between early chum spawning on the creek and watershed-wide chum escapement. “If we see a lot of chum in Yelm Creek, we’ll also see them later throughout the watershed,” Troutt said.

Tribal managers have been testing the model for the last few years.

“We’re excited by how accurate the model is,” Troutt said. “Despite a low run of chum last year, the number produced by the model was within a few percentage points of the eventual watershed escapement.”

To protect weak runs, the tribe has fished an entire chum season only once in the past eight years. The tribal fishery typically runs from late November to mid-January. Last year, for the first time, the tribe did not open a winter chum fishery at all.

“Winter chum has always been the most important stock to the Nisqually Tribe,” said Farron McCloud, chair of the Nisqually Tribe. “They were always our largest run and we depended on them to sustain us through the winter. We want to make sure enough salmon make it up the river to spawn.”

Nisqually tribal spawning surveyors hunt for chum salmon in Yelm Creek in early December. Photo: E. O’Connell