London Wildlife Trust is urging Londoners to report sightings of the globally-endangered stag beetle which is most common in the south east and south west of the city.

The stag beetle is Britain’s largest land beetle, almost 8cm in length, and is easily recognised by the male’s distinctive antler-shaped jaws.

Although the male beetles look fearsome they are harmless to humans, instead using their massive jaws to wrestle with other males when looking for a mate.

Despite stag beetles being in steep decline across Europe, London remains a hotspot and the Trust is asking the public to report their sightings, to help researchers map their whereabouts and numbers.

Stag beetles have been recorded in most London boroughs, but are more common in south and west London, from Bexley, Lewisham and Southwark to Wimbledon, Richmond and Uxbridge.

Three sites – Epping Forest, Richmond Park, and Wimbledon and Putney Commons – are European Special Areas for Conservation for stag beetle.

Researchers still don’t know why there have been relatively fewer sightings across north and east London, which is why people’s sightings are so important.

May is the start of the ‘stag beetle season’, which lasts until late July, although a cold spring can delay emergence.

The decline in stag beetle numbers is attributed to the tidying up of parks, gardens and greenspaces and the removal of tree stumps and dead wood.

Without dead wood the beetles have nowhere for their larvae to grow.

Stag beetles may be inadvertently destroyed in the mistaken belief they are pests, and in urban areas traffic, feet, cats and other predators can also have a negative impact.

If you think you’ve seen a stag beetle, or the related lesser stag beetle, click here.