- Lifespan
- Approximately 2–3 months as adults in the wild
- Size & Weight
- Body length 42–46 mm; wingspan 70–80 mm
- Habitat
- Fast-flowing rivers, streams, and occasionally larger watercourses with clear water and suitable bankside vegetation.
- UK Distribution
- Found in southern and central England, Wales, and the Midlands; resident species with emergence occurring in summer months (June–August), with highest abundance in July.
- Diet
- Carnivorous; hunts small flying insects in flight, including midges, flies, and small mayflies.
- Prey
- Small flying insects such as Diptera (flies) and small aquatic insects captured during aerial hawking.
- Predators
- Robber flies, larger dragonflies, and insectivorous birds such as darters and flycatchers.
- Mating Season
- June to August
- Breeding
- Females lay eggs in strings or clusters on the water surface or submerged vegetation; nymphs are aquatic and typically take 1–2 years to develop depending on water temperature and conditions.
- Behaviour
- Males are highly territorial and perch prominently on waterside vegetation or exposed stones to patrol their stretch of river. They exhibit aggressive chase behaviour towards rival males. Females visit the breeding habitat mainly to oviposit, typically in the early morning.