The first showing of caddis tells me it is finally spring here in the mountains of Idaho.
This event happened last week, along with a big spike in the water level of the Henry’s Fork. And now, with the world greening around me, I am fully engaged with a changed behavior of trout as it applies to feeding on or near the surface.
Along with increased depth, reduced water clarity has weakened the demand for intense precision as the rainbows and browns feed almost recklessly on the first sizable insects of the year.
Generally speaking, the fish are holding within a few feet of the bank, which means battling heavy currents toward mid-stream is not required.
Often casting from the bank, I will fish a floating caddis adult or emerging pattern when working upstream.
Fishing a slightly submerged pupal pattern with a twitching action on a tight line is a good method when working downstream.
In either instance, I will focus my attention on the 6 to 8 feet of water closest to the bank unless a rise appears further out.
Trout looking for caddis and concentrated close to the edge by high water are also a perfect setup for fishing from a drift boat.
The size 14 caddis that appear at this time of year are not considered large until they are compared to the insects that precede them. A size 18 Baetis mayfly is on the upper end of the scale, and most are smaller. And it is rare to get away with fishing a midge larger than size 22.
From this point forward until mid to late September caddis flies will be a staple on the Henry’s Fork and most other streams in the Rocky Mountain west. At no time, however, are they more appreciated than at the end of a long winter when the season truly begins for the fly fisherman.