Backstroke swimmer data sheet
Latin name:
Notonecta glauca
Trade name:
Backswimmer, Common Backswimmer
Origin:
Europe, Central Asia, China, Eastern Siberia
Size (in cm:
13.5 to 16 millimeters
age expectation:
1 to 2 years
behavior/stocking
Location at the pond:
Anywhere on the water surface
Dangerous?
Rather annoying for humans Ben Sale from Stevenage, UK, Notonecta glauca (29705232687), CC BY 2.0
Anyone who creates a pond in their own garden often does so to offer various plants and animals a nice home.
But every pond owner knows only too well that a pond here in Germany can not only attract friendly guests, but also annoying small animals, such as the so-called backstroke swimmer.
The typical features
The backswimmer is a (especially in this country) frequently occurring pond dweller, which is particularly noticeable because it is almost exclusively in the water propelled swimming belly side up.
This behavior is also the reason why the Belly of backstroke swimmers is much darker in color than their back. On this dark belly side are fine black hairswith the help of which the backstroke swimmer a bubble can hold. This air bubble then takes on the function of a “replacement gill” under water, which allows the backswimmer to breathe under water for a short time.
The body is mostly roof-shaped and overall rather greenish to brown colored. The sex cannot be determined quite so easily, since the males and females are pure externally almost indistinguishable from each other. Therefore, the gender can be determined based on the behavior fasten (egg laying etc.).
behavior at the pond
Backswimmers are among the pond dwellers that come in handy everywhere in the pond swim around and (apart from the water surface itself) have no preferred location in such a biotope.
The animals swim on their backs because of their long hind legs, with the help of which they move forward by rowing. In addition, the animal spends a lot of time on it, simply without any movement to hang on the water surface. It supports itself from the surface both with the abdomen and with the front legs.
This behavior is also an important part of hunting strategy. Once close to the surface small tremors from potential prey are to be perceived, these prey animals are caught by the backswimmer snapped up immediately.
Furthermore, these water creatures also have the ability to fly. This is how they settle in a garden in the first place. Once born in a body of water, they usually climb onto the shore, dry their wings, and then head off to new waters.
Feed & Nutrition
The Notonecta glauca is a little robber. He feeds primarily on different insects and larvae. his victim he encloses with his front legsto then his to sink the proboscis into the captured animalafter which the victim is stunned with a paralyzing poison, allowing the backswimmer to easily drain them.
Her favorite victims include, among others isopods, water spiders, tadpoles and mosquitoes. However, backstroke swimmers don’t shy away from it, either People to attack with their proboscis.
This puncture is referred to by most people as a quite painful felt, and in some cases can also lead to one local inflammation to lead. These painful stings are also the reason why backswimmers are popularly referred to as “water bees”.
Propagation & Breeding
The mating season for backswimmers begins in spring. A female stings various aquatic plants, whereupon it then up to 200 eggs deposited in the plant tissue. The resulting larvae make up to early summer altogether four developmental stages until they molt one last time just before reaching sexual maturity.
Externally, larvae differ only in their small body sizeas their other external characteristics are those of adult specimens relatively similar are.
The «breed” of these animals turns out to be quite simple, since basically all you need is a well-kept pond with some aquatic plants, and sooner or later some backswimmers will be attracted to the pond (and possibly continue to breed there).