Our house is full of places
where animals live and overall we are happy with that and it rarely causes any
actual harm although occasionally something dies which needless to say can
smell a bit.
Fortunately, as always, the
natural world is well equipped to deal with any small corpses that are
inaccessible, (as they invariably are), and Burying or Carrion beetles are one
of the insects that make their living from such things. There are some 20 odd
species in France with a total of 30 species in Europe
although not all are true burying beetles; some of them eat fungi or rotting
vegetation.
This year in September we
were finding Nicrophorus vespillo in
one part of our house and I would speculate that they had been on a dead Loir,
(Edible Dormouse), probably behind the bath or false wall in the downstairs
bathroom, one of the places where they frequently live. These amazing beetles
can smell a corpse from a vast distance using the highly sensitive hairs on the
ends of their club ended antennae. Having found a corpse, usually that of a
small mammal, both male and female set about preparing it for use, sometimes
excavating below it to bury it or even moving it if it’s small enough. Hairs or
feathers are removed as are any eggs or larvae of other species, (flies etc),
and the body is shaped into a ball where the beetles eggs are laid around it.
Both parents feed and care for the young larvae when they hatch and this can
last for up to 10 days before the young can consume the corpse directly. This
feeding of the young larvae by adults is very rare in the insect world and is
normally associated with social or colony forming species such as honey bees,
wasps and ants. In addition to this unusual behaviour the parents are known to regulate
the number of larvae in relationship to the quantity of food available on the
carcass by removing and killing some larvae if there is a shortage of food or
laying more eggs if there is plenty, thus having larvae of different ages on
the same corpse. Larvae pupate in the soil or debris under the corpse before
emerging between 20 and 30 days later.
Nicrophorus vespillo with mites
As with some other insects,
notably some Bumble bee species, these Burying beetles carry with them several
species of phoretic mites that use the beetle as transport from one corpse to
another. The relationship between these mites and the beetles has generally
been thought to be benign but there is extensive research continuing on what
the actual relationships and effects are. Needless to say it’s too complicated a
subject for me and to go into here but I’ve put a link below and to a great
video.
Chris
LINK Phoretic mites and beetles
LINK Video burying beetle at work and larvae