OK, size isn’t everything but the two largest moths we find
in France are
quite spectacular in both adult form and caterpillar and as such I think are
worth a mention, they rarely fail to rise a "wow" when someone finds one.
The Great Peacock Moth Saturnia
pyri is the larger of the two and is Euorope largest moth with a wingspan
of between 100 and 150mm, (4 to 6 inches), although some texts suggest that
200mm, (8inches), is possible.
Click on images to enlarge
Great Peacock Moth on my hand
This is a species with only one generation a year with the
adults usually emerging from mid April to mid May when they devote their short
life entirely to reproduction as they live for perhaps 7 days and have no
requirement to take nutrition.
Pair of Great Peacock Moths mating
Specifically a virgin female finds a place in a bush or tree
where she emits nightly sex pheromones which diffuse into the air which can be
picked up by males from as far as 5 km who will home in on the scent, however
only one male will get to mate with a female as coupling signals the end of the
pheromone emissions and sexual attraction.
It's always worth looking at any outdoor twine door curtains for eggs.
Due to the lack of time the female who is already bursting
with eggs will often lay them in the tree where she is as soon as they are
fertilised which is like as not in close proximity to where she emerged from
her chrysalis or cocoon which may even be the tree where she was an egg
herself. In some ways it’s of little importance as the caterpillar will happily
use a vast range of deciduous trees. The
caterpillar goes through 4 stages over 35 days before pupating and changes both
body colour and the colour of the tubercles.
Caterpillar last stage
They are to be found more or less all over France
if there are trees although there are far fewer towards the north.
The next largest moth is the Deaths head hawkmoth, Acherontia atropos, with a wingspan of
90–130 mm (about 3.5 to 5 inches), which makes it the largest European Hawk
moth, (Sphingidae).
Deaths head hawk moth Photo Philippe Mothiron.
Unlike the Great peacock this is not a French resident as
such, (yet), but a migratory species par excellence from North
Africa where it uses its huge wings to be carried on the air
currents across the Mediterranean Sea .
Generally the immigrants arrive in May-June and will
reproduce in the warmer south of the country where a second generation may be
produced in September or October. The caterpillars live for 3 to 5 weeks and
the pupal stage can last for about 3 weeks or so. Adult moths live for around 6 weeks and feed
on plant and tree sugars, sugars from fallen fruits and of course most
interestingly they can enter honey bee colonies and take uncapped honey even
though they are attacked by guard bees at the entrance to some extent but not
seriously, however the thick cuticle and resistance to venom allow them to
enter the hive or other colony space. Apparently they are able to move about in
hives unmolested because they mimic the scent of the bees. I’m not really sure
how this works as each colony has its own unique scent.
Caterpillars go through three stages, feed principally on
various nightshades, are frequently found on potato plants and can emit a loud
click.
Death head hawk moth caterpillars
Caterpillars from the second batch will find it hard to pupate
and even if they do they won’t survive the winter frosts.
Showing the skull like pattern on the thorax
The moths name is arrived at by the skull like pattern on
the thorax and it’s another species that was considered to be evil or a
harbinger of death. In France
they were quickly dispatched and treated with Holy water. What with that and
pesticides used these days on potato crops they haven’t had an easy time and
numbers have reportedly fallen significantly although if there are declines in numbers we would probably have to look to Africa and the situation there.
On the plus side, this year has been exceptional in France
with larger numbers of sightings of second generation caterpillars following a
very mild winter and a warm, dry spring and summer although again we should be cautious as the growth of social media and abundance of modern phones with cameras may simply be bringing to light larger numbers that would otherwise be missed.
Chris