Stag beetles are one of Britain’s largest and most striking-looking insects.  They are named for the male’s antler-like mandibles, which they to wrestle each other over mating territory in a way that mimics stags. Though they may look a little alarming, they’re harmless to humans.

Now it's stag beetle season, here’s everything you need to know about Lucanus cervus, and what you should do if you have them in your garden or home.

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What do stag beetles look like and when can you see them?

Males usually measure up to 7.5cm and females up to 5cm, though some grow as long as 12cm. Their head and thorax (middle section) are black and their wing cases are maroon or reddish-brown.

They spend most of their lives underground as larvae; adult females lay their eggs in or near rotting wood, which the larvae will feed on while taking between three and seven years to develop into adults.  At that point, normally between May and September, they emerge for a few weeks to hunt for a mate. You may see them in flight on warm summer evenings.

Where are stag beetles normally found?

Stag beetle on child's hand.

Stag beetles prefer to live in woodland, but may also be seen on farms, in hedgerows, parks and gardens.  In this country they are fairly common in southern England, but can also be found in the Severn Valley and in coastal areas in the South West; they are rare in other parts of Britain.

Stag beetle numbers have declined over recent years due to habitat loss, such as the removal of dead and decaying wood from parklands.  Because of this, the stag beetle is protected in the UK under the Wildlife and Countryside Act, 1981.

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What can I do if I find a stag beetle in my garden, or in my house?

If you find a stag beetle in your garden, you should leave it where it is unless it is in danger of being trodden on; if you do have to move it, or if you find one in your house and want to get it out, don’t take it too far – it’s best to put it in the nearest hedge. They are unlikely to bite you, but wearing gloves is a sensible precaution if you do have to pick one up.

Generally, stag beetles shouldn’t do any damage to your home or garden, but if you are able to keep any logs, stone piles and compost heaps (in which the beetles are likely to hide and feed) away from plants, they are even less likely to bother them. They are also attracted to light, so it’s sensible to turn off any external illumination if you want to keep them away from your house.

Have you seen stag beetles in your garden? Tell us in the Comments box below.