One of the things that a lot of beginning fly fishers don't naturally understand is fish behavior. When I'm guiding I like to spend a few minutes going over the basics of fish behavior. I find this helps the angler to focus their efforts better. If you don't understand what the fish are doing it's like chasing a moving target. Often, especially in lakes, fly fishing is actually chasing a moving target so understanding that is critical. Here are a few tips for understanding the behavior of several key fly fishing target species.
- Trout, grayling, whitefish, and many other species that live in rivers nearly always face upstream, they don't move very far from the same basic location, and they let their food come to them. This is why dead drifting flies to the waiting trout is so important. Trout generally seek out places with moderate current or places that have a rock or other debris that breaks up and slows the current.
- Salmon, steelhead, and other sea or lake-run fish move upstream fairly constantly but stop occasionally to rest in slower or deeper water on their way.
- Trout in lakes and many saltwater species like sailfish, marlin, tarpon, roosterfish, dolphin (Mahi Mahi), and dorado are relatively solitary and stay on the move. They move or cruise nearly constantly in search of food and to keep water passing through their gills.
- Many warm water species like bass, pike, muskies, crappie, and sunfish, along with some saltwater species like snook and barracuda are ambush feeders. They often like to sit still in weeds or other cover, or swim very slowly through cover waiting for their prey to make a mistake and then rush forward to quickly gulp the prey when it is close enough.There are occasional times where trout can act like this as well, sitting still near cover and ambushing their prey as it swims by. I've seen this behavior with brown trout, brook trout, and cutthroats.
- Many saltwater fish, including bonefish, permit, and redfish along with some freshwater fish, like carp are shallow water feeders or flats fish. These fish usually cruise shallow flats looking for crustaceans and other similar prey. When they locate prey it is usually on the bottom and these fish will go down to get it. In the process their tails often pop up above the water's surface. This is called "tailing" and it allows the angler to spot these fish.
- Many fresh and saltwater species like striped bass, white bass, wipers, some trout, and tuna are open water schooling fish. They cruise in schools seeking out schools of baitfish or other grouped forage items. If you can locate a school of feeding fish then the fishing can be fast and furious for a while until the school moves on.
Don't be surprised when a fish listed above does something totally different and know that these basic behaviors can be broken down much further into many more specific behaviors. However, this basic guide can definitely help anglers to begin to zero in on the fish they are after.