A Rebounding Trophy Fishery

Though Payette Lake has produced big Lake Trout for over 30 years, things weren’t always so rosy. In the early 2000s, biologists noticed signs of trouble. Lake Trout were getting thin from poor prey available, and the kokanee numbers – their main prey food item  – were dropping quickly.

“It wasn’t uncommon to catch a 30-inch fish that looked like a snake,” said Jordan Messner, Regional Fisheries Manager for Idaho Fish and Game in McCall. 

With the lake out of balance, Idaho Fish and Game launched a major plan to boost kokanee numbers while improving the quality of the Lake Trout population.

The Recovery Plan: Kokanee + Suppression = Restore Balance

In 2018, Idaho Fish and Game biologists started a two-pronged approach:

1. Stock more kokanee – to rebuild the prey base
2. Suppress smaller Lake Trout – to reduce competition and predation on kokanee 

The suppression program targets Lake Trout under 27 inches to remove them from the lake. So far, over 3,000 Lake Trout have been removed since 2018. The goal is to reduce the Lake Trout population to reduce competition and increase kokanee survival. With fewer mouths to feed, the remaining Lake Trout should be healthier and grow faster.

“We’re thinning out the juvenile Lake Trout so the ones that survive have more food – and they grow big,” said Messner. At the same time, biologists are working hard to stock more kokanee in the lake. 

Ongoing monitoring confirms the success of the strategy: average relative weight (a measure of how “fat” a fish is) has steadily improved since the program began.