Brown Hawker
Aeshna grandis
The Brown Hawker is one of the largest European dragonfly species. Its body is predominantly brown, with males exhibiting blue and females yellow spots on the abdomen. Unique are the consistently brownish-tinted wings, which distinguish it from all other native hawkers. It prefers standing waters with rich vegetation and is a highly skilled flyer.
Details
Identification
Wings distinctly tinted brown; brown thorax with two yellow lateral stripes; brown abdomen with small pairs of blue (male) or yellow (female) spots.
Social behavior
Solitary; males are territorial and aggressively defend their territories at the water body against conspecifics.
Diet
Larvae are predatory, feeding on aquatic insects, tadpoles, and small fish; adults catch flying insects such as mosquitoes, flies, and smaller dragonflies.
Hunting strategy
Larvae are ambush predators; adults are active aerial hunters, often catching prey at dusk or along forest edges.
Spawning substrate
Eggs are inserted endophytically into living or dead plant tissue as well as rotten wood along the shore.
Overwintering
Overwintering occurs as a larva in the aquatic substrate or on aquatic plants.
Ecology
Ecological role
Important predator in aquatic and terrestrial food webs; regulates insect populations.
Natural predators
Birds (e.g., Hobby), amphibians, larger dragonfly species; larvae are eaten by fish and aquatic beetles.
Competitor species
Other large hawkers such as the Southern Hawker (Aeshna cyanea).
Ecosystem service
Biological control of mosquito and fly populations.
Threats
Destruction of riparian vegetation, drainage of small water bodies, and use of insecticides in agriculture.
Scientific profile
Profile
Distinguishing features
The most important diagnostic feature is the brown-tinted wings, which distinguish Aeshna grandis from all other hawkers. In flight, the species appears overall very dark and brown. Males have a noticeably constricted abdomen base, while females are more cylindrically built.
Role in food web
Important predator in aquatic and terrestrial ecosystems; larvae are significant consumers in the benthic zone.
Protection & threats
Main threats
Loss of near-natural shoreline structures, intensive fish farming (high predation pressure), excessive eutrophication, and the drying up of small water bodies.
Population trend
Stable; the species is widespread in Germany and is among the more common hawkers.
Conservation measures
Protection and restoration of reed beds and floating-leaved vegetation; promotion of extensive pond management; preservation of riparian buffer strips.