Male stag beetles
grapple with their
‘antlers’, trying to flip
their rivals over or hurl
them to the groundthem easier to digest. Because this fungus cannot
survive in chalk regions, could its absence be acting
as a barrier to the beetles? But the same fungus is also
found in the north of England, where there are no stag
beetles, so other factors may be at play.
Another possible explanation is that the species
reached the limits of its current British range in
the last ice age. There is a suggestion that because
the adults don’t feed, the species is limited in how far
it can disperse.
Breeding battles
Whatever the reason, this is a gem of an insect to have
so close to the urban sprawl. Having spent up to seven
years living in dead wood as larvae, the adults at last
emerge to breed, lay eggs and die, usually within
the space of a few weeks. Only the males have antler-
like mandibles. They emerge before the smaller
females to establish a territory, and use their massive
jaws to attract mates and for stag-like territorial
rutting with rivals.
The best time to see them is at dusk in May,
June or July. The lumbering males fly
clumsily in circles to defend their territory,
and they may be picked up on bat detectors,
which emit a wonderful clicking sound as
they buzz past. The beetles are drawn to
windows lit up after dark and you can also
tempt them to land with soft fruit. The short-
lived adults don’t eat, but they enjoy tree sap and
fruit juice, particularly mango, licking it with their
orange tongues.
Males use
their massive
jaws to attract
mates and
for stag-like
territorial
rutting
with rivals
In medieval times, stag beetles got a bad press:
they were said to summon thunder and lightning,
and to visit fires to steal hot coals and set buildings
alight. Their many names included thunder-beetle,
billywitch, devil’s imp, horny bug, cherry eater,
oak-ox and horse pincher.
Sadly, these days they are better known for
the decline in their population. Habitat loss and
fragmentation are key problems, while roadkill
and predation by magpies have an impact, too.
Human ignorance also plays a part: many of us keep
our gardens far too tidy, putting down paving and
decking, building greenhouses and removing the tree
stumps and dead wood in which stag beetles breed.
Some people even mistake them for cockroaches and
stamp on them on the pavement, oblivious to the years
they have spent underground, waiting for their few
weeks of glory.| SAVE THE BEETLESNATURE