Backswimmers are a common aquatic insect, known for their distinctive swimming style. These small creatures typically navigate water bodies on their backs, using their long hind legs like oars. While generally not harmful, they can deliver a painful bite if handled, often compared to a bee sting.
Natural Homes of Backswimmers
Backswimmers thrive in a variety of freshwater habitats across the globe, with around 400 species identified worldwide. They commonly inhabit still or slow-moving water bodies such as ponds, lake edges, marshes, and streams. These insects prefer environments with ample aquatic vegetation, which provides both shelter from predators and a suitable place for hunting their prey.
Backswimmer Life Cycle
The life cycle of a backswimmer involves three main stages: egg, nymph, and adult, following an incomplete metamorphosis. Adult females typically lay their elongated eggs on or within submerged aquatic plants, or sometimes on rocks, usually during spring and summer months. The hatching time can vary from a few days to several months, depending on the specific species and environmental conditions.
Once hatched, young backswimmers emerge as nymphs. These nymphs generally resemble smaller versions of the adult insects but lack fully developed wings. They undergo several molting stages, known as instars, gradually growing and developing their wings before reaching their adult form, a process that can take several weeks to months.
How Backswimmers Travel
Backswimmers move efficiently through water using their long, oar-like hind legs, which are fringed with fine hairs for propulsion. While they typically swim on their backs, they are also capable of flight. Adult backswimmers possess functional wings, allowing them to leave one water source and fly to another. This dispersal often occurs at night, as they search for new habitats, food sources, or mates.
Their ability to fly is an important mechanism for colonizing new water bodies, even isolated ones. This aerial mobility allows them to move away from drying ponds, overcrowded areas, or places with limited food.
Why Backswimmers Appear in Human Environments
Backswimmers frequently appear in human-made water bodies like swimming pools, bird baths, and garden ponds due to several attracting factors. A primary reason is their attraction to artificial lights at night. They may mistake the reflection of lights on the water’s surface for natural bodies of water, leading them to fly into pools.
These insects may also seek out new water sources if their original habitats become unsuitable, such as during droughts or when natural ponds become overcrowded. Swimming pools, with their clear water, can be perceived as suitable new homes. Backswimmers are predatory insects, feeding on other small aquatic insects, mosquito larvae, and sometimes even tadpoles or small fish. If a pool contains algae or other smaller insects like water boatmen, it can provide a food source, further attracting them. Their presence can also be a result of accidental entry.