1/1-1/18/21 Report: Leech Game Strong

CONDITIONS AND APPROACH

The leech game has been strong!

Here are some comments about what I’ve noticed recently: for those that haven’t been out, the creeks are super low still. The snow is promising for a good recharge (of springs and shallow aquifers) but with only minimal melt (due to sub-freezing atm temps) the creeks aren’t actually getting fed by much groundwater support right now. These low conditions in combination with higher Summer/Fall harvests last year are causing for a lower retention rate of trout in their typical Winter holding areas. There are still fishable numbers in most of the Decorah streams, but you will certainly have to put in some extra footsteps to put together a quantifiable day on the water (not uncommon for Winter fishing). I certainly think a lot of fish have been pushed around to find more suitable water (which is why you’ll find some holes with 20-50 fish in them).

The issue this creates is that it concentrates all the fishing to these very limited pockets of productive water. Limited suitable water results in longer stretches between fish holding areas. So the way to avoid fishing the same pod of fish all day is to cover more water. Find more of these congregations to put more fish in the net; the reality is that you’re probably only going to be able to entice a handful of fish at a time to actually eat from these “fish bowls” (small area with a high density of fish).

SELFISH HERD THEORY

In order to achieve the highest success in these "fish bowl"-type scenarios you really need to know where these holes and pockets are, prior to approaching the spot. When you are scouting and learning to read the water and watching the behavior of these fish, you'll notice that many of these are actually moving and shift quite often. These fish are not going to be worth your time because they are not actively feeding. Due to strong intraspecific competition for ideal space and access to food lanes, the most dominant (and well fed) fish are going to be closest to the middle of the pod where it is the safest. This behavior is proven by a theory called the Selfish Herd Theory. So if we apply this theory to our "fish bowl" scenario, the outermost positions will be the most vulnerable, and will subsequently be the least likely to have access to adequate food lanes. The low water conditions have already decreased overall flow and consequently the biomass of suspended food.

This prior knowledge will help you approach the pod of fish with a more critical lens and hopefully lead to higher success. Target the outmost positioned fish to elicit the most aggressive response. These notes for me have come by lots of time observing trout behavior and critically analyzing social hierarchies of group behavior. Pretty cool stuff to be able to apply when conditions get tough.

FLIES AND TECHNIQUES

Given the evaluation of our current conditions, it is important to reiterate that low flow=less floating food. Most aquatic bugs (i.e. caddis, stoneflies, burrowing mayflies, clinging mayflies, scuds, etc.) are not very efficient swimmers, which is why one of the only ways for trout to be able to have access to them is in-drift or suspended in the current. The most widespread occurrence leading to suspended bugs is the increase or sustaining of discharge through a stream or river. So if most of the bugs are staying on the bottom and not readily available as food, then trout will be forced to shift their foraging behavior (which they are quite used to under most conditions anyway) in order to find food. This means that hatches (the emergence of aquatic macroinvertebrates) will become more critical as a process that suspends bugs in the water column, making them accessible as food.

This also means that the abundantly smaller group of bugs that are more efficient swimmers or movers (i.e. leeches, dragonfly larvae, cranefly larvae, swimming mayflies, maybe scuds if they decide to swim, etc.) will become a crucial and sought-after food source for these competing trout. Using flies like the MAK Leech, Mayer Mini Leech Jig, or classic buggers are great options for these scenarios.

Long story short (haha), don't be afraid to animate your flies a little bit during these low flow conditions. Try some leech patterns, emergers during a hatch, even swinging soft hackles might not be a bad idea right now either (just try to keep it low-and-slow). Euro Nymphing has been a lethal way to present flies on the bottom, or crucially low in the water column to elicit strikes. Jigging micro-streamers has been lethal and versatile even in picking up fish as we walk from spot to spot as well. Of course nymphs such as the MAK Caddis, PT Jig, and Brassie have produced well as droppers when using a micro-streamer as an anchor fly. Precision is key and details always matter lol.

FINAL THOUGHTS

Accessible fish are sparse right now and details can make a good day into a great one, but hopefully with a bump in flows we'll get to see some of these "fish bowls" disperse back out and maybe even get some fish to move back into the creeks from the bigger water systems. I still think that the increased number of anglers over the last year will not be decreasing anytime soon and that we are seeing a noticeably concerning decline in populations across the Iowa Driftless for retention of trout on public waters. I recognize that fish do move a lot (and trust me, this I KNOW), so we won't see the full impacts of last year's harvests, post-spawn die-offs, late Summer heat impact, etc. until this Spring.

However, I want to reiterate that the way that our management system (legislative controlled, rather than expert controlled) is currently setup, Iowan fisheries will tap out in being able to support the strikingly evident increase in trout fishers every year. The fact that people have to keep spots a secret in order to protect it tells us that our management system is incompetently designed. To know that our management system is run on SECRECY is not sustainable and truly upsetting to me. STEWARDSHIP education must be at the forefront of this movement as we welcome new anglers because that is how we are going to set the foundation for LASTING change. I come from a family of educators and the way that my culture has taught me is through a 7th-generation mindset, that we should be making every decision with the goal that there will be enough for the future 7 generations and beyond. I will expand more on this topic in a future post. In the meantime, please learn about how the Iowa management system works and educate yourself, then your children about how to be the best caretakers and lovers of the land that we can be.