It is the middle of summer and a fly angler's mind is filled with thoughts of savage hopper eats. Or something sort of poetic like that...
For the fly angler, terrestrial flies provide some of the most enjoyable and productive fishing of the season. Grasshoppers certainly get the most publicity but ants, beetles, crickets, and other terrestrial insects can be more important at times. The only thing I enjoy more than fishing terrestrials are the caddis hatches of the late-spring and early summer.
Project Terrestrial is going to explore some of the how and why behind fishing terrestrial flies. See the end of this post for a preliminary - and likely to change - overview of Project Terrestrial posts.
Why Terrestrials?
Aside from terrestrials being fun as can be? Do you really need more than that? OK - then let's dig into the why...
Let's get started with the idea of reciprocal prey subsidies - which was my first ever post on this blog. I think it is one of the coolest ideas about how streams interact with their terrestrial surroundings. The idea is that streams and their riparian zones (terrestrial area along streams that have a strong influence on streams) reciprocate in the energy each provides to the other. Simply put, in the summer, terrestrials entering streams is an important energy source for predators in streams (fishes, mostly) and in the spring and fall, adult aquatic insects provide much of the food for birds, bats, spiders, and other terrestrial predators.
This image is from a paper from a 2001 Nakano and Murakami paper (https://www.pnas.org/content/98/1/166) from Japan is probably the best example of the concept of reciprocal prey subsidies. Read the post on reciprocal prey subsidies for more details and analysis of seasonal changes - it is a three minute read, I will wait...
Panel D from the 2001 Nakano and Murakami paper (https://www.pnas.org/content/98/1/166) is the important one for the fly angler. Terrestrials peak in June through October or November and aquatic prey items dominate in the winter and early spring. In general, terrestrials are larger than aquatic macroinvertebates so that makes them more efficient for trout to feed upon. It takes a lot of craneflies or Grannoms to equal the biomass of a size 14 beetle or a grasshopper. Optimal foraging theory at its best.
Small streams are ideal for fishing terrestrials. Our streams are relatively narrow in width and relatively shallow. Because they are small, terrestrials are of greater importance. As I had written about in the post on the river continuum concept, as stream width increases, the influence of the riparian zone decreases. Likewise the relatively shallow depths mean that terrestrials that enter the stream are seen and felt by trout in the stream. In big rivers, terrestrials may only be important within a few feet of the bank, a small percentage of many western rivers. In most Midwest streams, terrestrials are important from bank to bank - though you probably want to keep them relatively close to the bank.
What Terrestrial to Fish?
We all have our favorite patterns and even our favorite things to imitate. I like beetles and crickets more than most. Others go for ants and hoppers. Terrestrial fishing may not be the most fast and furious fishing of the year but it can be some of the most fun. Hopper eats are often explosive and savage whereas fish feeding on ants are often slow and deliberate. Unless you happen to be fortunate enough to encounter a flying ant "hatch", in which case all bets are off and you are likely to experience some amazing fishing.
Observation is the key to figuring out what terrestrial to fish. Look at what, if anything, is moving as you are walking along the stream. Terrestrial insects also have their own habitat preferences. Grasshoppers are more common in tall grass prairies and ants and beetles are generally more common in woody/shrubby riparian areas.
If I am thinking about what a terrestrial "hatch chart" looks like, ants and beetles are out by April and increase in importance in May and June. Grasshoppers are small in June - I am imitating them with caddis patterns early on. Depending upon the year, July through mid-September is prime hopper season. Crickets tend to come on a bit later and last a little longer into the fall. Ants and beetles have been there all season but for me at least, I am fishing them a little more in September through the end of the season (mid-October).
Want to find fish eating grasshoppers? You need to go to where the grasshopper are which mean ditching the comfortable, heavily grazed stream that is easy to walk along and find a stream that is lined with tall prairie. Hoppers have little to eat in those over-grazed pastures that we like because they are easy to walking and there is nothing to catch our backcast. "Matching the terrestrial hatch" means timing and riparian habitat. A day of grasshopper fishing tends to follow bankers hours. They do not get moving too early - they need to warm up a little first. And an hour or so before dusk, they start slowing down. Ants and beetles are earlier risers. A little wind always helps.
In addition to observation, experiment! Too many anglers decide that they are going to catch fish on hoppers today and stick with that plan when it is not really working. Give the hopper a bit of time and fish it in some likely looking places but if it is not working, try something else. Put on an ant, a beetle, or a cricket. Or downsize your hopper and see if that makes a difference. Fishing "western hoppers" on Wisconsin streams often does not work. If you are seeing grasshoppers along the stream, take note of their size. Rarely do I fish a hopper that is tied on a hook larger than a #10 hook and I would say that #12 or #14 on a 2-3xl hook is the "sweet spot" for hoppers in the Midwest most of the time. I am more likely to fish #14's or even #16's than I am #8 or #10's. Early in the summer, I am fishing #14's and #16's - or simply fishing a CDC and Elk caddis pattern or a stimulator and hoping it does "double duty". I move up in sizes as the season progresses but that is based on observation. Match the "hatch".
A few of my favorite places to fish terrestrials are Elodea chocked streams where fishes are concentrated along the edges of the weeds and are looking up for insects floating in the small channel between the weeds. They are not maybe the most productive places to fish but they offer a great challenge. I especially like these places when there are some trees along the bank where ants and small beetles are likely to be falling in the water once in a while. If you see something like in the above photo, ditch your hopper or "hippie stomper" and try a small ant or a beetle. And watch a bit before casting, particularly on a day with just a bit of wind, the fish are very likely to show themselves.
What Patterns to Fish?
Fish what you have confidence in and experiment a bit to find new confidence flies. I have always been someone that thinks fly patterns are pretty over rated. I am less concerned with what pattern I have tied on than I am how and where I am fishing it. For terrestrials, my preference tends to be to have some that float really well and I can fish anywhere and to have a few low floating flies. For hoppers, crickets, ants, and beetles, I will have a couple of versions for each. I love the Morrish Hopper for its simplicity and really accurate profile but I will have a few lower floating hoppers (Letort's, Whit, Dave's, Schroeder's parachute, etc.) for when the high floating foam creations are not being eaten. Same with the other terrestrials.
As I have gotten older, one near necessity on my terrestrials is something that helps me see then on the water - a bit of foam, a parachute post, or some other high visibility indicator. This is particularly important for the low-riding terrestrials. The flies above are not really a pattern yet but something I have been working on these last few years. They are tied on a "Klinkhamer" hook so the abdomen is down in the water and the X-legs and thicker abdomen give the fly a larger surface profile. Give it a try and report back - experiment and have fun, that is what tying should be about.
A lot of times, our terrestrial flies do not need to look like anything trout may have ever encountered. The Royal Training Wheel above looks vaguely food-like and floats really well. And it breaks many of the "rules" I have for terrestrials. It is too large for starters. Yet on this particular day, the fish wanted nothing to do with the dropper - so it came off - but they would move four or five feet to grab this gaudy fly. Experiment and have fun. Remember what works and do not discard what did not because each day is different.
Project Terrestrial Installments
Part 1 - Ants, Beetles, Hoppers, and Crickets, oh my!
Part 2 - Thoughts on Terrestrial Fly Patterns
Part 3 - To Foam or not to Foam
Part 4 - The Classics
Part 5 - All About Hooks
Part 6 - Sunken Terrestrials
Part 7 - Seasons of the Terrestrial "Bugs" - a terrestrial fly box
At least that is the plan for now. It is subject to change either due to feedback or my whims. I have no idea what the timing of these posts will be other than I would like to have the last installment out by the end of our fishing season (mid-October).
Comment below with anything you would like to see. I am hoping to experiment with some photography so these posts may be pretty sporadic depending upon whether or not I can get the shots I would like to capture.