Zircon Reed Beetle

The Zircon reed beetle (Donacia aquatica) is an attractive metallic rainbow-coloured beetle that can be found on sedges in early summer. It is a UK Priority Species that has greatly declined; having been lost from over 80% of its UK range. It is also the most threatened reed beetle (Donacia) in Britain.

Fast Facts

Latin name: Donacia aquatica

Notable feature: Reed beetles can be brightly metallic species and are often referred to as “jewels amongst the reeds”. The mainly green and red upper surface of the Zircon Reed Beetle and its golden underside should set it apart from other species.

Rarity in the UK: Rare / Common

Where in the UK: The Zircon reed-beetle was formerly widespread in wetlands across large parts of the UK. It is now restricted to Inverness-shire and a few other sites in England. It was recorded from Upper Lough Erne in Northern Ireland in 1992.

A perfect home

This species is associated with waterside habitats that are dominated by sedges, with adult beetles usually being found in small numbers on reeds and other emergent marginal vegetation at the edges of open water, including rivers, streams, ditches, pools and larger lakes.

Lifecycle

The adult beetles are active earlier than most other reed beetles, being visible between May and July. The adults tend to sit on the leaves of emergent vegetation and will lay their eggs at the base of these plants in early summer. The beetle is most often detected by chance by sweeping stands of aquatic vegetation, though adult beetles have a habit of dropping off plants or flying away when the foliage is disturbed!

Larvae are aquatic, feeding on the underwater parts of emergent vegetation. The larvae eventually form tough cocoons attached to the plant roots, within which the pupae will overwinter, and emerge as adults the following spring.

Why does this beetle need help?

The Zircon reed beetle has suffered widespread declines. It is a species sensitive to eutrophication and disturbance and is therefore a good indicator of habitat condition and overall site condition. The main threat to this species is loss of or disturbance to its marginal sedge bed habitat as a result of eutrophication, encroachment of water margins and excessive management from drainage, water abstraction and infilling of lakes and ponds.

What is Buglife doing to help?

Buglife are working in partnership with the Lough Erne Landscape Partnership (LELP) and others to complete a pilot study of Lough Erne’s reed beetles, undertaking essential survey work to gather population and distribution data and develop local species recovery plans. We will then work with landowners to make sure that the correct conditions for the Zircon reed beetle are present to help this species recover. Buglife is currently running a citizen science survey to help find out what the current distribution of this species is- details can be found here.

References and further information