Nature, Uncategorized

What Do Stoneflies Eat?

Stoneflies eat algae, plant material like algae, and small insects.

Nymphs have a mouth section that is used for chewing and they mostly live on plant material. Others are carnivorous and eat small aquatic invertebrates.

Many species of this fly lose the ability to eat when they form the adult feature. Then others still have their mouthparts, and they can eat even when they are adults.

Stonefly nymphs have different eating preferences based on their life cycle and the source of foods.

The nymphs are opportunistic eaters, which means they eat whatever is around them. While other species find the things they want to eat. The carnivorous nymphs stab the prey and use their mouth section for grinding and scraping.

As an adult, very few species of this fly can eat, and in this time they mostly concentrate on mating.



Are They Dangerous

Adult stoneflies have no mouth section that can bite or eat. The large flies are entirely harmless. A stonefly can become 0.25 to 2.5 inches. Their presence is a good thing on the water as the fishes get their food. Adult flies are poor fliers and normally do not go beyond the water source, but some of them venture half a mile from the stream. These flies do not live a long life once they reach adulthood, eventually, their numbers reduce in one or two weeks.

Generally, stonefly isn’t a predator, but fishes eat them. Also, fishes aren’t the only predator out there to consume these flies.



Where are stoneflies found

There are various streams where these flies can be found. This is the natural habitat of this insect. As nymphs their natural habitat are springs, flowing streams, clean water, and rivers. They are usually found at the spots where the current is brisk. These flies creep under the rocks and other submerged things in the water, these insects prefer quiet waters like ponds and lakes.

Larger and adult ones stay close to the shady areas and water sources. This is because they are poor fliers and can’t fly far away. Some of these roam around at night times and get attracted by bulb lights.



how big a Stonefly become

Stonefly has 2,000 species, and they have a long antenna, two pairs of wings with membranes, chewing mouth section. A stonefly can range in size from 0.25 to 2.5 inches. Their hindwings are larger and smaller than the forewings, and they fold like a fan when the insect isn’t using them. Even with fully developed wings, an adult fly is a poor flier. Many species of this insect are found in brown, black, or gray. Just so they can blend in with nature.



Fly fishing with Stonefly

Nymphs are usually used for fly fishing. These are mostly used to catch trout throughout the year. Different species of this fly spend two to four years at the bottom section of the river, and they are the best forage for various trout species. Even during the winter fishermen catch this fish with stoneflies. It’s best to use smaller flies.

The best to fish with these flies is when they are getting out of the water. The moment they are crawling or swimming through the current, trout concentrates on these flies. Fishes are found at the edges as they hunt and feed on flies. It’s important to note that during the hatching time of these insects fishes become picky, so it’s best to follow realistic and detailed patterns.


There are some simple ways to get stonefly nymphs. The first and most crucial step is to catch them under the strike indicator. To do this, you have to tie two flies to the fly leader, then add a short split shot while you are fishing in deeper water. This makes sure the flies reach depth quickly.



How to Get Rid of Stoneflies

Stoneflies commonly stay at the bottom of the streams and rivers. These are important flies as fishermen use these as bait for fish. They use this insect to draw trout through the entire year. However, if your house or property is infested with this insect, then it’s hard to get rid of the flies. Some of these species get attracted to artificial lights and they tend to fog the source of illumination making it hard to see the surroundings. However, the emergence of these flies happens only for few days after that they grow old to return to the water source.


Moreover, to get rid of these insects, you have to turn off the outside lights. Or install a yellow illumination which is called bug light. For commercial buildings should use sodium vapor lights than mercury ones. While it is so little you can do to prevent the flies, there are steps you can follow to minimize their breeding.

You have to replace the mercury vapor lights with sodium vapor, also use yellow bulbs instead of the white lights. It’s also important to install screens for windows and doors and install them properly so the flies don’t get to enter. If the situation is out of your hands, contact pest control.



Stonefly is a member of the Plecoptera order, and these are different from caddisflies and mayflies. They can be differentiated by the their wings which are made of four membranous and held flat over the abdomen section.

The antennae of the flies are thread-like and long. Adults have two thin and long appendages from the top of the abdomen. As for immature nymphs, they are mostly found in rivers and streams. They are important insects of the ecosystem, serving as the food for water animals. Adult stoneflies emerge from the water in spring and winter times. Many fly species fly at night and get attracted to lights.


Stoneflies are an important part of ecosystems. As they make good food for the fishes they are also used to catch fish throughout the year. They mostly eat algae.