It’s early August and we are coming into prime terrestrial season here in Southwest Montana and the Greater Yellowstone Area. Terrestrials provide epic dry fly fishing in the late summer when the abundant insect hatches dwindle.
What is a terrestrial? A terrestrial is simply an insect that is born and spends its life on the land, rather than hatching from the river. These bugs live near the river banks and occasionally fall into the river, providing trout a potential food source. The most popular example would be a grasshopper, but it also includes ants, beetles, and many other insects that live on land but may accidentally fall into the river.
The terrestrial season makes for some fun late summer fishing, though it comes with its challenges. I have had my fair share of struggles over the years catching fish on terrestrials, so I thought I’d share a few things that have helped me catch fish during this time of year.
Here are a few tips for fishing during the terrestrial season here in the Yellowstone region. I hope you get out and apply one of these tips before the cold nights bring an end to the summer fishing season here in the Greater Yellowstone Region.
Tips for Fly Fishing Terrestrial Season
Do not ignore the other terrestrials.
When many anglers think of terrestrial season, the grasshopper is what first comes to mind. This is for good reason. Fishing a big foam hopper can yield some epic eats and some of the biggest fish of the year.
Though, it is not the only terrestrial I keep in mind when on the river during the late summer months. Ants and beetles have become just as important in my fishing. They often fool the pickier fish as many fish have already been caught on a variety of grasshopper patterns.
Do not forget about crickets and spruce moths as well. These insects can be random but are abundant on many of the streams out west. Trout are opportunistic feeders, especially when the hatches are thin. I like to be prepared with a variety of terrestrial patterns so I can take advantage of whatever situation I find myself in on the river.
Foam Is Not Always The Answer
Many of the best terrestrial patterns on the market today include foam as the main material. Foam terrestrials are great flies as they float easily and take little effort to keep floating. I like foam flies for terrestrials as they splat onto the surface and get the trout’s attention. Don’t get me wrong, foam flies are great options for all terrestrial fly patterns.
They are not always the answer though when fishing terrestrials. It pays to have a few flies without foam in your box that include natural materials. Since so many anglers are fishing foam all season long, a more subtle fly tied with natural materials can do the trick when your foam flies are being refused. These flies land lightly on the water, ride lower in the water column, and seem to offend fewer fish in my experience.
A few of my favorite non-foam terrestrials include the CDC flying ant, moose hair beetle, and the parachute hopper. Whatever you prefer, keep a few of these flies in your box through the terrestrial season and find out why they are so effective.
Sink It
Terrestrial season means low flows and pressured fish. These trout have seen flies all summer long and are usually at their pickiest point during the late summer months.
A trick that has helped me fool some of the pickiest trout during these times is sinking my fly. Whether it be an ant, beetle, or hopper, a sunken terrestrial seems to fool the trout that otherwise couldn’t be caught on the surface.
How do I do this? I either spit on it, neglect to dress the fly with floatant, or tie terrestrial patterns with the intention of them sinking. More often than not sinking a terrestrial pattern gets the job done on the spookiest of trout.
Add a Dropper
Only so many fish in the river are willing to come to the surface on a given day to eat your dry fly. It ebbs and flows throughout the late summer on good and bad terrestrial days. Tying a nymph dropper off the back of your dry fly will help smoothen out those periods when the dry fly fishing is slow.
Many of the terrestrial patterns today include foam and can float tungsten bead nymphs below the dry fly. I tend to fish my droppers with 3 to 5 feet of tippet, playing with a variety of patterns until I come to one that is working. Though I wouldn’t think twice to put a short dropper on and fish it in shallow water as that can provide some epic shallow water sight fishing opportunities.
Give The Fly Action
Have you ever seen a real grasshopper in the water? Very rarely do they float down the river without some movement or twitching. Twitching my hopper patterns over the years has made for some fun dry fly fishing and can be the trick to fool more fish during the terrestrial season.
Whether it be a fast riffle or a slow-moving backwater, a small twitch to your hopper or terrestrial pattern is worth a try. The natural bugs kick and twitch when they fall into the water and the fish key into it. A little movement can go a long way in enticing the fish to take your fly.
A few tips when fishing your terrestrial patterns with a twitch. I have found that this works best with foam flies as they float better. Non-foam flies tend to sink when moved in the water. Also, the smaller the movement the better. Erratically skating a terrestrial is not natural to a trout and is likely going to get refused. A few small, light movements of the fly is all you need.
Fish Early, Leave Early
My last tip for fishing during the terrestrial season is to get out on the water early and be back home by mid-afternoon. The terrestrial season coincides with the hottest weather of the year. This leads to dangerously warm water temperatures for our trout friends. Catching them during these times can put excess stress on the fish and increases the mortality rate of fish released.
It is also smart in the sense that your best fishing will be when the water temperatures are coolest. I’ve found that my best fishing in August occurs between 8 am and noon (if not earlier some days). The afternoons can be hit or miss depending on the watershed and its water temperatures. Fish early, leave early, and abide by any fishing closures in your area. It’s best for the fish and your success fishing.
I hope a few of my tips for fishing during the terrestrial season help you catch more fish as the summer comes to a close. These strategies have worked for me over the years, though I wouldn’t be surprised if you have other tactics that work for you. I’m always looking to connect with other anglers and learn as we all have different experiences on the water.
There is nothing better than catching a big brown trout on a hopper from an undercut bank. It’s what terrestrial season is all about and why us anglers get so excited for this time of year. I hope one of these tips helps you experience this time of year to the fullest.
