Stepping into the garden at nine o'clock on a warm May evening I become aware of a buzzing sound. Directly in front of me, two male stag beetles fly clumsily in circles before crashing into the wall and dropping to patio.

They have probably detected a female nearby, wafting her potent pheromones into the evening air. The males will fight using their  massive 'antlers', the victor claiming his prize.

My garden has been a hotspot for stag beetles ever since a large sycamore next door was felled years ago.

Eggs are laid in decaying timber, in this case the rotting roots of the tree. Grubs live for up to seven years munching on dead wood, finally reaching the size of a man's little finger and pupating.

Adults emerge in late May and June, active for about an hour around dusk and live for about two weeks, lapping up tree sap and moisture.

Beetles are prone to predators, targeted by crows and magpies. Once I saw a fox leap into the air in an effort to catch one.

I even watched a wasp rip off a beetle's wing cases, legs and head to get at the soft flesh below, chewing off pieces to feed its grubs.

Badgers also dig up beetle larvae.

When filming a TV commercial involving fighting stag beetles we noticed that as battle commenced under the powerful arc lights each male puffed out a fine jet of mist from its rear end, something never observed before in stag beetles.

However, another beetle, the bombardier, is well known for ejecting a volatile liquid like a puff of smoke when threatened.