Let's explore the beneficial, beautiful, busy, and bemusing world of bugs! Bugs form the backbone of a heathy ecosystem, all without possessing one themselves. Most bugs you are likely to encounter on a spring evening live most of their lives in the water as macroinvertibrates (creatures without a spine that you can see with your naked eye). These adorable little “macros” perform a variety of functions for a heathy stream.
Macroinvertibrates can be broken down into categories on what they eat, and how. Grazers generally collect loose material on the bottom of a stream and are not discerning, eating most anything smaller than their mouths or processing algae and other microorganisms. Filter feeders collect almost exactly the same types of foods as the grazers, but tend to collect their food using filtering mouthparts. Predators, as you would expect, hunt their food and feed on most other things smaller than they are. Another group known as shredders, do not cruise around in streams on skateboards and snowboards as their name suggests. Shredders process larger material into finer parts, often times they make homes out of this detritus, and are key in decomposition of almost everything that falls into a stream.
There are members in all of theses groups who are only in the water for portions of their life-cycle. These stages can be one of several steps as they progress into adulthood, sometimes changing into another semi-aquatic critter before fully transitioning. Aquatic oddities aside, most people experience these friends in their adult stages as they franticly search for their true love.
Many species of insects have adapted to emerge from their aquatic stages in huge numbers to better their chances of finding a mate before being consumed. These hatches occur near the same time every year, though especially off-season weather can cause mini-hatches to occur early or late. The most infamous of these are the various species of mayfly that hatch along Spring Creek. This frenzy takes place just above the water’s surface, attracting an abundance of fish and therefore an abundance of fishing enthusiasts.
The mayflies can collectively form large balls that catch the evening sun in spectacular ways. These masses of mayflies often mate and die within minutes of hatching, providing essential food for many species of water-side birds and almost every cold-water native fish.
Stoneflies too, follow a similar emergence process. Though their numbers are often less dramatic, a warm spring evening near a stream can be filled with them if conditions are right. Identifying them in flight is difficult, even for trained professionals, but once they land on a surface it is fairly easy to tell the two varieties apart. Mayflies tend to hold their wings vertically and away from their bodies while alighted on an object, whereas stoneflies hold their wings down and parallel to the body segments.
As spring transitions to warmer and warmer temperatures the number of large hatches declines and many other species begin to emerge from their nymph stages. Chiefly among them are dragonflies and damselflies. Often mistaken for each other, they both posses the classic two-winged look and can move acrobatically through the air. The key difference in their adult stages is the way they hold their wings. Damselflies will always bring their wings together when they land, while dragonflies keep their wings flat at all times.
In their aquatic stages these bugs are nearly pinnacle predators. They have specially designed mouthparts that can unhinge and extend to consume almost anything smaller than they are, and able to inflict pain on some things that aren’t. Some retain these alien-esque mouths and continue to feed on smaller insects even after their transition.