Large yellow underwing
The large yellow underwing moth does exactly what it says on the box; it is one of the largest of Britain’s moths and is easily identified by its yellow underwings, bordered with black. If disturbed as it rests during daylight, it flashes the bright orange-yellow of its underwings in an attempt to scare off any predators.
It is possibly the most numerous of our larger moths, found all over the British Isles. Its numbers are sometimes swelled by migrants coming from southern Europe. It isn’t known yet what triggers the migratory behaviour but some years the influx can be enormous.
In most of its range the large yellow underwing (Noctua pronuba) flies at night between June and October. It is highly attracted to light, sometimes in very large numbers and it is usually among the moths circling the outside lights in your garden or blundering around your bedroom when you have left the light on and the window open.
Late instar caterpillar of large yellow underwing.
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