Beetle mania

Calderdale Moorland Group

Like many areas of moorland recently, Calderdale has seen an explosion of Heather Beetles (Lochmaea Suturalis).

A normally widespread and common insect that can be found across the country, Heather Beetle populations can expand into large outbreaks in which large areas of heather are damaged.

The larvae of the beetle feed on the leaves of heather plants, stripping them bare and thus damaging the plants. Adult beetles will also do this.

In a normal year small patches of heather may suffer from beetle damage, showing as rusty red areas instead of healthy plants.

The beetle is present on most moorlands in the UK in low numbers. Adults hibernate over winter in the plant litter/seed layer of the heather and emerge in spring to climb up the heather and move on the wind. Where there has been an outbreak the previous year, high densities may be seen the following spring and with the milder winters we are experiencing recently more are surviving to the following year.

April and May are the favourite months to see the adults as the breeze moves them. Eggs are laid from April-June with larvae emerging from June-August. The adults die after breeding.

The larvae will feed on the heather till ready to pupate and then emerge as new adult beetles in August to feed and grow before going into hibernation from November.

As the Heather Beetle likes damp conditions they favour areas of heather with sphagnum mosses.

The population explosion this spring is a worry for our keepers as grouse chick's need nutritious green heather once they come off insects to survive and the Adults need it to keep in good condition.