Distinguished from other large eggar moths by the diagonal cross line on the forewing and two small white spots. Males are usually a warm reddish-brown with yellowish patches. The females are larger and can vary in colour from deep yellow to very pale buff, whitish or a darker reddish-brown similar to the male. In the fens of East Anglia, the males are often yellowish.

The adults fly at night and are attracted to light, the males especially.

Fully grown caterpillars are up to 7cm in length. They are dark grey with golden speckling and have brown hair tufts along the body. A line of white hair tufts is present on either side of the body.

The caterpillars hibernate when part grown and continue feeding in the spring, becoming fully grown by June. In winter they can sometimes be found at rest on grass stems and on the twigs of bushes. In the spring they feed mainly at night, but during the day can be found resting low down on vegetation.

Flight Season

Flies between July and August in one generation.

Size and Family

  • Family – Eggar moths (Lasiocampidae)
  • Large Sized
  • Wingspan Range – 42-70mm

Conservation Status

  • UK BAP: Not listed
  • Common

Caterpillar Food Plants

A wide range of coarse grasses and reeds including Cock’s-foot (Dactylis glomeratus), couches, Common Reed (Phragmites australis), Reed Canary-grass (Phalaris arundinacea) and Wood Small-reed (Calamagrostis epigejos).


Most frequent in tall, damp grassland, fens, marshes, damp open woodland, scrub and ditches. Sometimes occurs in drier habitats, including urban gardens.


  • Countries – England, Wales, Scotland and Ireland
  • Well distributed throughout England and Ireland, becoming more coastal north to Northumberland and on the western side of mainland Scotland. Rare on the Isle of Man and Guernsey. Widespread and abundant on Jersey.
Drinker - Ryszard Szczygieł


Drinker (female) - Garry Barlow

Drinker (female)

Drinker (male) - Garry Barlow

Drinker (male)

Drinker (female & male) - Patrick Clement

Drinker (female & male)

Drinker (male) - Koen Thonissen

Drinker (male)

Drinker (female) - Koen Thonissen

Drinker (female)

Drinker (eggs) - Patrick Clement

Drinker (eggs)

Drinker (caterpillar) - Ryszard Szczygieł

Drinker (caterpillar)

Drinker (caterpillar with dew) - Heath McDonald

Drinker (caterpillar with dew)

Drinker (caterpillar face) - Bob Eade

Drinker (caterpillar face)