Aeshna grandis (Linnaeus, 1758)
Common name: Brown Hawker
Preferred environment: mesotrophic and eutrophic, sheltered lowland lakes and ponds. Also canals and flooded disused gravel pits.
Flight period: end of June to the end of October. In Ireland end of June to mid September
Adult habitat and habits: males are territorial holding territories at water bodies or away from water. Copulation occurs away from water in vegetation.
Oviposition site and behaviour: females oviposit alone placing eggs into wet mud, wet deadwood or aquatic and marginal plants.
Larval habitat and habits: eggs overwinter and hatch in spring. Larvae live amongst submerged water plants or amongst plant debris. Development takes 2-4 years according to locality. Recorded food items include chironomid larvae (up to 50% of diet in some studies), adult flies and Zygoptera from water surface. Larvae can also be cannibalistic.
Emergence behaviour: emergence happens low down on marginal vegetation at night.
Range: northern and central Europe from the Pyrenees to northern Finland; Asia to Lake Baikal region. Common in central Ireland in lowland areas, but very local in western and southern Ireland and upland areas.
Determination of adults: species is keyed and male abdominal appendages are figured in Askew (1988). Mature adults are illustrated in colour in Askew (1988) and Brooks (1997).
Determination of larvae: Askew (1988)
|Nelson, B., Thompson, R. & Morrow, C., 2000 (May 2). [In] DragonflyIreland http://www.ulstermuseum.org.uk/dragonflyireland/|