Birch bug

Birch Shield Bug (Elasmostethus interstinctus)

When we opened the moth trap the other morning, we found this colourful bug trundling around among the egg boxes. It's a Birch Shield Bug (Elasmostethus interstinctus), and it's another new species for the garden. Like many other shield bugs, it sucks the juices out of plants — in this case, primarily (and appropriately) the catkins of birch trees. Presumably, it was attracted by the Silver Birch at the foot of the garden; it will also feed on hazel, if it can't find birch. It's widespread throughout the British Isles, as well as across Europe, North America and northern Asia. A smaller version of the Hawthorn Shield Bug, it lacks the pointier projecting "shoulders" of its larger cousin, and what projections it does have are seldom red-tipped. It also shows more red on its scutellum (the triangular plate in front of the wings), and at the tip of the abdomen (just visible under the wings in the picture above). Though adults are found from May through October, they are most common in early autumn. They'll hibernate in leaf litter overwinter, emerging next spring to lay their eggs. Formerly considered to belong to the "stink bug" family, they've now been moved to the "parent bug" family, Acanthosomatidae. Females guard their eggs, and travel with their young for at least part of their lives. We'll have to keep a closer eye out for them on the birch next year.