Diving Beetle (Dytiscus sp.)

Diving beetles make up a large group of aquatic beetles that are common in ponds and quiet streams.  These beetles get air at the surface but can remain submerged for long periods because they carry air in a chamber under the elytra (the first pair of wings).  They often hang downwards from the surface of the water.  These insects may leave the water at night and fly to lights.  Both adults and larvae are highly predaceous, feeding on a variety of small aquatic animals, including small fish.  The larvae, often called water tigers, have long, sicklelike, hollow jaws, with which they grab prey and suck out the body fluids.  These larvae are very active and will not hesitate to attack an animal much larger than themselves. 

Availability: These need to be ordered and will be available after spring break.

Housing: They can be kept in a large jar, bucket, or aquarium with aged tap water that is at least two inches deep.  Be sure to put a lid on the container because they can fly and you do not want to lose your project.  Put some plastic, or real, aquatic plants in the container for the adults to hold on to.  You can add some stones or mud to anchor the plants down with.  Change the water when it starts to become soiled, or cloudy.

Food: You can feed them living amphipods, brine shrimp, other aquatic insect larvae, or anything smaller than themselves.