Small Eggar

Eriogaster lanestris

Eriogaster lanestris, commonly known as the small eggar, is a moth of the family Lasiocampidae that is found across the Palearctic. Unlike many other members of the Lasiocampidae, the small eggar is a social insect. Historically, only eusocial insects like ants, bees, and termites were thought to exhibit complex social organization and communication systems. However, research since the late 20th century has found that E. lanestris, among a number of other phylogenetically related moth and butterfly species, demonstrates social behaviors as well. Larvae spend nearly their entire development in colonies of about 200 individuals, and this grouped social structure offers a number of benefits, from thermoregulation to increased foraging success. Source

Where it is now

No records in the last 8 weeks. It may be out of season where the observers and sensors are.

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Movement and weather

Over the weeks it was present in the past year, its centre in Europe ranged from 48°N in May to 63°N in April, about 1,600 km apart.

Arrival dates

The week it was first heard regularly in each region, after at least six weeks away. Dates differ from south to north, so a region has a range.

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Figures are effort corrected and come from automatic sound identification, which makes mistakes. How this is measured and how it compares with human observers.