What do dobsonflies eat

Food The larvae are predaceous and snatch nearly anything that swims or ambles by, including other aquatic insects, small fish, and so on.

Status This is the only species of dobsonfly in eastern North America. Life Cycle Life Cycle. Dobsonflies are long-lived insects. The larvae typically live for 2 or 3 years underwater before pupating and becoming winged adults. Egg masses are laid on branches or rocks next to streams. These masses resemble bird droppings, which protects them from predators. After hatching, the larvae crawl or fall into the water, where they spend the next 2 or 3 years.

Once grown, they crawl out of the water, form a cocoon, and overwinter. They emerge in spring as adults and usually only live for a few days after that.

The adults focus only on reproduction. The large tusks of the male are used for clasping the female during mating. They should be grasped behind the head, lest they deliver a painful pinch. The enormous, imposing adults are rarely seen, since they are short-lived and nocturnal, but they are an awesome sight. Meanwhile, there are plenty of fish that relish these larvae, which explains their hiding under rocks!

The adults, once they have reproduced, become food for birds and other animals. One of our collecting sites is next to a good sized river so perhaps we will be able to attract a few Dobsonflies to our black light sheet. Wish me luck.

I was the Fresno County Entomologist for 30 years. I fielded calls from the general public, pest control companies, farmers, PCA's, etc. I developed a , insect specimen collection for the county over the 30 years that I was there.

I received my Ph. I now enjoy working in my garden, traveling with my wife, golfing and bowling, take insect collecting trips in the US and overseas in the tropics, and work on some personal research of some small wasps. You are currently not signed in. If you have an account, then sign in now! Anonymous users messages may be delayed. Name required. E-mail required. Dobson Flies. Protect your home or business from dobsonflies by learning techniques for identification and control.

Keeping pests out of your home or building is an ongoing process, not a one-time treatment. Orkin can provide the right solution to keep dobsonflies in their place and out of your home or business. Dobsonflies are found primarily outdoors near large bodies of water.

Dobsonflies develop in running water and are an important insect that adds value to the overall quality of aquatic ecosystems. While this means properties near streams and rivers experience more activity from the pests, it also ensures that they rarely come into homes. At most, homeowners might notice adult dobsonflies around outdoor lights. An open window near a light source may encourage one of these insects to come inside.

Adult male dobsonflies have long, curved mandibles, but they are harmless to humans. Females and larvae have smaller, sharper pincers that can pierce human skin. Despite their frightening looks and size, these insects are not a danger to people. Dobsonflies only bite when handled roughly, and while the bite is painful, the effects of a bite do not last very long.

Additionally, these insects are not known carriers of any diseases, and they may emit unpleasant odors when threatened. The life-cycle of this species is strongly affected by temperature -- in the southern part of the range they can complete a generation in less than a year, but further north it may take years. Adults only live for a few days -- females die after laying their eggs. Anderson, Only parental investment is in choosing egg-laying site, and provisioning eggs. Corydalus cornutus takes one to three years to complete its life-cycle.

Anderson, ; McCafferty, Corydalus cornutus larvae and adults are most active in twilight or at night. Except for mating, they are not social. Larvae mostly crawl, but can swim forward or backward by undulation. Adults are sometimes attracted to artifical lights at night, and may fly some distance from their emergence site. Hellgrammites, the larval stage of Corydalus cornutus , probably rely mainly on touch and chemical sensing to locate prey. They do have eyes though and can at least detect motion and shadow.

Adult male dobsonflies have scent glands on their abdomen that apparently play some role in mating. They also lay their mandibles over females when courting them, so touch is relevant too. Hellgrammites, the larvae of Corydalus cornutus and other corydalids , are active predators that feed on a wide variety of small stream invertebrates, including insects and other arthropods, small worms, and small molluscs.

They are generalists, whose diet choices probably reflect relative abundance of different prey types rather than specialization. They are known to particularly feed on blackfly larvae Simuliidae and the larvae of net-spinning caddisflies several familiies in the Trichoptera and mayflies Ephemeroptera.

Adults are not believed to take solid food. Females are reported to feed on nectar from flowers, males are not believed to eat at all. Corydalus cornutus avoids predators by limiting its activity in daylight, by hiding, and by biting in self-defense if necessary. Adults and larvae are cryptically colored.