No.036 · Butterflies, moths and other insects · Uncommon
Stag beetle
Lucanus cervus
Britain's largest beetle. The males' antler-like jaws are for wrestling rivals, and they fly, slow and heavy, at dusk on warm summer evenings.
When to look
June to July, mostly at dusk.
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Time of day
- Dawn
- Day
- Dusk
- Night
- Best time
- Warm evenings from mid-May, peaking around June–July, when males fly at dusk looking for females. The adults do not survive the winter.
- Where in the game
- the New Forest (ancient woodland and lawn)
- Size
- Males 35–75 mm, females 30–50 mm (PTES)
- Lifespan
- Adults live only a few weeks in summer; the larva takes at least 3–4 years underground (PTES)
- Population
- No reliable total; widespread in southern England, but extremely rare or extinct across most of Britain outside it (PTES)
- Status
- Nationally Scarce (PTES); UK priority species
Diet
Larvae eat rotting wood underground. Adults cannot eat solid food and drink sap and fallen fruit.
Habitat
Woodland edges, hedgerows, parks, old orchards and gardens with rotting stumps and logs.
Breeding
Females lay eggs in rotting stumps and logs; larvae live 3–4+ years before pupating.
Field signs
- A large, dark beetle flying low and slowly at dusk, with legs dangling
- Large 'C-shaped' cream grubs in rotten stumps
- Dead males or female remains on paths
- Males gathered on a fence post or tree at dusk
Did you know?
- The male's 'antlers' are enlarged jaws used for wrestling rivals, not for biting or eating (PTES).
- The larva lives underground for 3–4 years or more, while the adult lives only a few weeks (PTES).
- PTES lists the New Forest as one of the places to watch for stag beetles, thanks to its ancient woods and plentiful dead wood.
Moments worth waiting for
- Males wrestling
Two males lock jaws on a log and heave, trying to flip each other, while a female watches.
Photo tip
Choose a warm, still evening in June and be at a wood edge or garden an hour before sunset. Shoot at eye-level, side-on on a log, with a 100 mm macro. Use natural light or gentle diffusion for males in flight.
Be a good naturalist
Handle a beetle only if it is stranded, moving it gently to a shady log. Never collect or keep them. Leave dead wood and log piles alone: it is the larvae's habitat, and one of the best ways to help them.
The law
Wildlife and Countryside Act 1981 Schedule 5: protected from sale only (section 9(5)), not from killing. Rotting wood is its home, so leave stumps in place.