An unused swimming pool becomes the home of many freshwater plants and animals. Insects of many types, such as beetles (Coleoptera), true bugs (Heteroptera), and fly larvae (Diptera), can be observed swimming in unused swimming pools.
Here a Dytiscus beetle has flown in from a neighbouring pond to make the pool its temporary home. It surfaces rear-end first to breathe before diving again to hunt for prey. Diving beetles are excellent swimmers, their bodies are streamlined, and their flattened rear legs, which bear two rows of “swimming” hairs (see photo), can generate powereful strokes.
A disused swimming pool is great place to observe freshwater wildlife because it is easily accessible, its edges are free from terrestrial vegetation which often make it difficult to see. In addition to this the blue of the pool allows us see creatures that we might not have noticed - check out the spiral of green algae in the photo.
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