Lakes are too hot for late-summer trout releases
Why is it that the Oregon Department of Fish and Wildlife refuses to stock area lakes during the summer, precisely when lake use is highest and the interest in catching trout to cook is also at its highest? Do they think people fish for trout in the spring?
- J.R., Medford
In fact, they really want those trout to go home in coolers (albeit only at legal limits), and that’s one of the reasons fish aren’t stocked in the summer.
The water’s often too hot. And this year, also too low.
Dan VanDyke, ODFW’s Rogue District fish biologist, points out that rainbow trout are coldwater fish that thrive in temperatures up to the mid- to upper-50s.
Water that reaches the mid-60s causes concerns that the already stressful handling, loading and releasing of trout may increase that stress and cause more fish to die, VanDyke says.
Moreover, warmer water holds less dissolved oxygen for trout, making it even more difficult for trout to adapt to their new environs and survive, he says.
During summer, water temperatures in the ponds, lakes and reservoirs of the Rogue watershed can often exceed 70 degrees.
The local exceptions to this are the Rogue River upstream of Lost Creek Lake, where cool water flows year-round, and Fish Lake, which has some cool-water springs.
That’s why the Rogue and other water around Union Creek are stocked weekly through the summer, and Fish Lake is tapped to get another 3,000 fresh legal-sized rainbow trout through last weekend.
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