Backswimmer (family Notonectidae), any of a group of insects (order Heteroptera) that occur worldwide and are named for their ability to swim on their backs.
The most common genus of Backswimmers is Notonecta – streamlined, deep-bodied bugs up to 16 mm long, green, brown, or yellowish in colour. N. maculata, is distinguished by its mottled brick-coloured forewings.
Backswimmers swim on their backs, vigorously paddling with their long, hair-fringed hind legs and attack prey as large as tadpoles and small fish. They can inflict a painful "bite" on a human being (actually, similar to a mosquito "bite", it is a stab with their tubular mouthpart). They inhabit still freshwater, e.g. lakes, ponds, marshes, and are sometimes found in garden ponds. Although primarily aquatic, they can fly well and so can disperse easily to new habitats. They seem to be attracted to light; similar to a moth drawn to a flame. For instance, if a Backswimmer enters a swimming pool with an LED light seen under the water, it will inspect the light by swimming up close to it and never leaving that spot.
In contrast to other aquatic insects that cling to submerged objects, Anisops deanei uses a unique system to stay submerged: using the extra oxygen supply from haemoglobin in their abdomen, instead of using oxygen dissolved in the water. The size of these air bubbles, which provide buoyancy, changes as the nitrogen dissolves into the blood and the oxygen is used in respiration. This allows for regulation of the size of the air bubbles and their concentration of oxygen.
How to Get Rid of Water Bugs:
The backswimmer and water boatman. These pests are in the aquatic insect classified under the order Hemiptera. The bugs generally are not harmful to humans, although the backswimmer in particular can deliver a painful bite. Although most bugs feed on algae, the backswimmer feeds on the water boatman as well as other bugs. None of the bugs can live outside of the water for long periods of time, so getting rid of their food supply and nesting places stops bugs from living in the pool.
To get rid of water bugs; attack their way of living. Chlorine and shock treatments are not effective at killing them or controlling their population. In order to eliminate them, one must better understand them and their preferred environments.