A Rare Treasure- Norfolk Hawker

Latin name: Anaciaeschna isosceles

Image result for norfolk hawker
Image of a Norfolk Hawker courtesy of Jackie Dent

The Norfolk hawker is, and has always been, one of Britain's rarest dragonflies and is under heavy protection, due to its place on the red list for endangered species. An occasional visitor to campus here, at UEA, the hawker has largely been confined to fens and marshland, leading to government initiatives to restore and protect these habitats. Such action has overseen a greater spread in the hawker population in East Anglia and the recolonisation of sites where they had previously disappeared. They are restricted to small pockets in East Anglia and are very rarely found elsewhere in the British Isles.

Appearance wise, the hawker displays several distinctive characteristics including clear wings, green eyes and a yellow triangular mark on the second abdominal segment. The average hawker dragonfly measures approximately 67mm.

During the reproductive cycle, mating primarily takes place upon emergent vegetation before the female deposits her eggs into water, where they settle on aquatic plants, in particular water soldiers. Here, the eggs develop in to larvae over the duration of two years until the flying period is reached, by which time the larvae will have grown to a length nearing 45mm . The flying part of the life-cycle typically lasts between May and August each year.

Dragonflies, including the elusive hawker, tend to consume small invertebrates such as damselflies, with the name 'hawker' derived from their predatory behaviour involving tracking down and scanning for suitable prey to devour.

Being such a rarity in this country, the hawker is in a persistently precarious position, a status driven by a variety of threats to this fascinating invertebrate. During the last century over 30% of grazing marshland was drained and converted to arable farmland. This reduced the amount of suitable breeding sites for the hawker while also polluting vital water courses. This has led to a much needed increase in cleaning of dykes around East Anglia in a bid to enable and encourage the breeding of hawkers. With initiatives such as this, the future of the hawker is finally looking much brighter.

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