Summer heat brings many changes, and for trout anglers, understanding how it affects fish behavior is crucial. Recently, a guest at the Beardsley House on the river reached out with a common question about trout fishing in warmer conditions. He described a trout inspecting his spoon lure but then turning away, wondering if his reeling speed was the issue. While reel speed can be a factor, temperature often plays a more significant role, especially during the summer months.
Northern Michigan offers plenty of options for August heat showcasing a small stream surrounded by lush greenery.
The Impact of Warmer Temperatures on Trout
This summer has been relatively mild, especially compared to a prolonged cold and wet spring. However, consistent daytime temperatures, combined with higher lake levels and minimal rainfall to cool rivers, are pushing water temperatures in rivers like the lower Boyne River into bathwater territory.
For trout, particularly brook trout, rising water temperatures present a challenge. They are cold-water species and will actively seek out pockets of cooler water, often found near spring inputs, as thermal refuges. Brown and rainbow trout may migrate upstream to riffle zones, which typically have higher dissolved oxygen levels, aiding their respiration in the heat.
This period highlights the importance of responsible angling and considering the 70 Degree Pledge. When water temperatures approach or exceed 70 degrees Fahrenheit, the stress on trout increases dramatically.
A close-up shot of a vibrant brook trout displaying its beautiful colors and patterns.
Ethical Angling in Warm Water
As I explained to the inquiring guest, angling for trout in warm water can be detrimental, even fatal, to the fish. In warmer temperatures, the energy expended by a trout during a fight can lead to a buildup of ATP in their muscles. Even if released, these fish may not recover. It’s a matter of conservation to leave trout in these conditions undisturbed.
Instead of targeting trout in easily warmed waters, anglers should consider pursuing warm-water species like bass and bluegill. Alternatively, exploring smaller, less prominent streams marked as thin blue lines on maps can be highly rewarding. These smaller feeder creeks, such as those found in the upper Jordan or Manistee River near Deward, often remain significantly cooler, rarely exceeding 62 degrees. These areas can still hold plenty of trout eager to take a fly, offering excellent fishing opportunities with lighter tackle like a 3-weight rod and dry flies such as a Chernobyl Ant or Hippie Stomper. These smaller streams, shaded and spring-fed, provide the cooler, oxygen-rich environments trout need to thrive even when the summer heat might seem to be drawing flies elsewhere.
