Common Water-Boatman

<em>Notonecta glauca</em>, commonly known as the common water boatman, is an aquatic insect belonging to the family Notonectidae within the order Hemiptera. This predatory bug is widely distributed across Europe, with confirmed presence in Belgium, Denmark, Norway, and Sweden, and is classified as Least Concern on the IUCN Red List, reflecting its stable and broadly distributed populations. The species typically inhabits standing or slow-moving freshwater bodies such as ponds, lakes, ditches, and marshes, where it is well adapted to life just below the water surface. It swims on its back, using its elongated hind legs as oars — a distinctive behavior that makes it immediately recognizable. <em>Notonecta glauca</em> is a carnivorous predator, typically feeding on small invertebrates, tadpoles, and occasionally small fish, which it subdues using piercing mouthparts that inject digestive saliva. The species is capable of flight and can colonize new water bodies when existing habitats dry out or deteriorate. Biological traits including average lifespan, body length, and weight remain poorly documented in standardized databases, though adults are typically a few centimeters in length. The common water boatman plays an important ecological role in freshwater food webs as both predator and prey, contributing to the regulation of small invertebrate populations in lentic ecosystems across its range.