Aquatic Entomology

mayfly

For those of you that fly fish or even tie flies...especially for trout, it is often not enough to know that a particular insect is a "flying bug". Many of the more common aquatic insects favored by trout have several "life stages" that are important to understand and be able to imitate and present to the fish in a way that encourages the fish to eat it. The "life stages" can vary between different types of aquatic insects so it will be covered in each of the specific groupings that follow.

For those of you that fly fish or even tie flies...especially for trout, it is often not enough to know that a particular insect is a "flying bug". Many of the more common aquatic insects favored by trout have several "life stages" that are important to understand and be able to imitate and present to the fish in a way that encourages the fish to eat it. The "life stages" can vary between different types of aquatic insects so it will be covered in each of the specific groupings that follow.

I should note here that these often subtle changes in a trout's feeding behavior are much more common to mayflies than when other insects (caddisflies and stoneflies) are the food of choice. The reason for this I think, it that the life cycle of the mayfly is more complex than that of the other main aquatic insects. Mayflies have more "stages" than do these other bugs so there are more situations that you need to be aware of.

For many years, I carried a small aquarium net in the back of my vest. If you are going to try to fool a trout, it is a very good idea to know what "fish food" is available to the fish in the particular section of the stream you plan to fish. By simply sitting by the edge and carefully watching the surface, you will start to see what is available to the fish. However, as most food a trout takes is underwater, you will need to know "what's down there?" That is where the net comes in. Simply hold it on the bottom and start turning over rocks and moving the gravel around. Shortly, you will know what the fish have available subsurface. Once you know a little entomology and can identify what you have found, you are well on the way to fooling a fish. Here is a video to demonstrate..."Match the Hatch"  by Ken Tanaka of Wish4Fish.

I have been very fortunate to have friends that even know all of the Latin names of these bugs. I will share some of that information here. I will do my best to keep the Latin to a minimum.

NOTE: If you are interested in aquatic insects or you like to tie nymphs, here is a site for you... lifeinfreshwater.net. There are incredible images of virtually all of the nymph or underwater forms of aquatic insects.

NOTE: Should you be interested in capturing and saving aquatic insects from the river/stream, to use when tying nymphs, here is a short video that explains the process very well...see it here...

For more detailed information on...

Mayflies...

Caddisflies...

Stoneflies...

Terrestrials...

Other "flies"...

Entomology is the branch of zoology that deals with the study of insects. In this case, entomology as it relates to insects (mostly aquatic) that trout and other species favored by fly fishers eat as a regular part of their diet. As a primarily "trout guy", much of this will revolve around mayflies, caddisflies, stoneflies (aquatic) and the array of terrestrial (insects "of, on, or relating to the earth"). Examples of terrestrial insects are ants and beetles.

Recommended Books on Aquatic Entomology...

Dave Whitlock - Guide to Aquatic Trout Foods

Aquatic Entomology by W. Patrick McCafferty