Let’s Talk Bugs
by Tom Lager

The other evening at the Fox Valley Chapter’s Fly Tyer’s Demo I was having a discussion with Mark Peerenboom about late season fishing techniques and experiences on the Oconto River. Mark’s enthusiasm for the river and interest in its fishes convinced me I needed to return to those waters and explore them for myself. On my way home, I decided Friday was the day – in fact the last day before the “orange warriors” would own the woods and all running water there in for at least several weeks.

I was in the water early; the hydraulic pressure of the river collapsed the waders against my legs, transferring the November chill. I pulled on my fingerless gloves and readjusted my collar. The sight of clean redds on raised gravel beds assured me of my location. The across and down rhythm kept me warm and the awareness of the potential take kept me focused, well at least for awhile, until I noticed the midges.

Tiny, fragile, flying mechanisms buffed around in a cold wind. No other bugs were on the wing – just these little creatures. They skim along within centimeters of the surface going back and forth. Others hover on your leeward side, out of the direct wind, landing on your rod or vest, permitting close examination. I bring the rod up close to see the males with their plumose antennae, but in a flash they are off. Apparently, not in the least affected by the cold temperatures – my fingers were stiff and slow – but not their wings.

Researchers reveal that some midges like Diamesa mendotae, common to the upper mid-west, are winter active. That is emerging, mating and laying eggs in winter. The temperatures common to these activities are below freezing, under extreme conditions they survive near 0 degrees Fahrenheit. How can this be achieved?

Some strategies involve production of antifreezes. These may be antifreeze proteins or chemical antifreezes, such as glycerol (sounds like what I put into my radiator), which function to depress the freezing point. Another approach is the ability to supercool - that is remaining liquid well below freezing temperatures without formation of ice crystals – accomplished with cryoprotectants, such as amino acids and methylamines. Scientist continue to explore these mysteries of His making, in spite of considerable progress in understanding subzero temperature adaptations in insects. One such group is located at the University of Minnesota – no surprise there, they take advantage of their cold winters – where midges are of particular interest to the Chironomidae Research Group.

As I think this through, I cannot recall many fishing experiences under cold weather conditions in which I did not see

midges on the wing – especially on those cold-windless sun light days. In fact as you look at emergence calendars midges are available in all seasons and in virtually all aquatic habitats. Refer to Ross Mueller’s book “Flies that catch trout” pages 40-46 for fly examples with meaningful commentary; he does not talk about winter midge fishing, but has some nice winter pictures.

I love the feel of the two-handed rod, but I really need to improve the technique. After hours of casting, my legs were numbed as I walked from the river but I was content, it was a good day. Mark was right; it is worthwhile understanding this river – it pushes you to look and observe, to turn the rock and to marvel at the smallest winged critter while you are there for the big ones.