Finding bugs in swimming pools is common. While their presence can be unsettling, understanding these creatures helps with effective management. Various types of bugs enter pools due to their natural behaviors and the pool’s characteristics.
Identifying Common Pool Bugs
Several types of insects frequently appear in swimming pools, each with distinct features. Water boatmen (family Corixidae) are small, brown, oval-shaped insects that swim right-side up using their oar-like hind legs and often have noticeable parallel crosslines on their backs. They are typically found near the water’s surface, sometimes making a buzzing noise. Backswimmers (family Notonectidae) are often mistaken for water boatmen but are usually larger, dark brown or black, and swim upside down with their long, hairy hind legs. Their bodies are slender and streamlined, resembling the keel of a boat, and they may appear silvery due to trapped air bubbles.
Predaceous diving beetles (family Dytiscidae) are another common sight, characterized by their shiny black, brown, or dark olive bodies, sometimes with yellowish markings. These beetles are efficient swimmers, propelling themselves with powerful hind legs that move simultaneously, and can range in size, with some growing over two inches. Mosquito larvae, often called “wrigglers,” are aquatic and have large heads, fuzzy thoraxes, and narrow, worm-like abdomens; they hang just below the water surface to breathe through tubes. When disturbed, they “wriggle” downward. Mosquito pupae, known as “tumblers,” are comma-shaped and also float at the surface, though they are mobile and can move with jerking motions. Other small insects like gnats, midges, springtails, and thrips are also found, with springtails being tiny, dark, wingless insects that jump long distances.
Why Bugs Are Drawn to Pools
Bugs are attracted to swimming pools for several reasons, often mistaking them for natural bodies of water or finding them suitable for their life cycles. Pools provide a readily available water source, especially in dry climates, which can attract various insects seeking hydration. Nocturnal insects, such as predaceous diving beetles and backswimmers, are often drawn to the reflection of light off the water’s surface at night, mistaking it for suitable habitat.
Accidental falls account for many terrestrial insects like ants, spiders, and grasshoppers ending up in pools. Mosquitoes, for instance, lay their eggs in stagnant or still water, and even a small amount of standing water can become a breeding site for them. Water boatmen are drawn to pools because they feed on algae and other microscopic organisms. Backswimmers are attracted to pools where water boatmen are present, as they prey on them.
Potential Risks from Pool Bugs
While many bugs found in swimming pools are harmless, some can pose minor nuisances or health concerns. Most insects are simply an aesthetic issue, making the pool less inviting. However, some aquatic insects can deliver painful bites or stings if provoked. Backswimmers, also known as water wasps, are known to bite, and their bite can feel similar to a bee sting. Predaceous diving beetles, though generally not aggressive towards humans, can also bite if mishandled.
Mosquitoes are a significant concern due to their role as disease vectors. They can transmit diseases such as West Nile virus, Zika, dengue, and malaria, making the elimination of mosquito larvae in pools and surrounding areas important for public health. While thrips do not bite, their “probing” can cause a pinprick sensation, itching, or a slight rash. Allergic reactions to insect bites or stings are rare from most pool bugs.
Effective Pool Bug Management
Effective management of bugs in swimming pools involves both preventive measures and removal techniques. Regular cleaning and skimming help prevent bugs, as removing leaves, debris, and other organic matter eliminates food sources for bugs like water boatmen and reduces hiding places. Maintaining proper chemical balance, including appropriate chlorine levels and pH, also helps, as a well-maintained pool environment is less hospitable for many insects and can help prevent algae growth that attracts bugs.
Using a pool cover when the pool is not in use can significantly reduce the number of bugs entering the water. Trimming vegetation around the pool reduces resting spots and potential entry points for terrestrial insects. Addressing outdoor lighting that attracts nocturnal insects by turning off lights near the pool at night or using less attractive light sources can help deter them. Eliminating all sources of standing water nearby, such as in buckets, clogged gutters, or tarps, is essential to prevent mosquitoes from breeding. For removal, manual skimming is effective for visible bugs. Using a pool vacuum helps remove debris and bugs from the bottom, and regular backwashing of filters can clear out trapped insects. Increasing water turbulence with return jets can also help surface bugs sink into the filtration system. For severe or persistent infestations, professional pest control services can be considered.