Processionary caterpillars have started building their nest in SE Qld

Caterpillars are starting to hatch from egg masses and ground nests are starting to form.

Newly developed ground nest

Caterpillars from separate egg masses laid close together are likely to join to become one big nest (see photo below). This nest was formed from 3 egg masses. It is common to find egg masses/nests on previously infested host trees (you can tell by the caterpillar frass (poo) and shed exoskeleton surrounding/underneath the current nest).

Developing ground nest on top of the previous season’s nest.

We have also found a few cases of ground nesting caterpillar egg masses laid in the tree fork which is uncommon since they usually lay on the tree trunk (see photos below). This egg mass has successfully developed into a nest above ground!

Ground nest developing on tree fork
Close up of the ground nest


Processionary caterpillar season starts in SE Qld.

Adult Bag-shelter moths (Ochrogaster lunifer) have been emerging from pupae during October and egg masses are starting to appear in areas where the moth is prevalent. There is 5 – 6 week window from egg lay to when the 2nd stage (instar) caterpillars start feeding in the tree canopy. Although only about half of the egg masses laid by female moths develop into caterpillar nests, this is a good time to remove any egg masses seen on properties that have the potential to cause problems later in the season. When removing egg masses observe all safety procautions including avoiding contact with skin and eyes, avoid breathing in the moth scales covering the eggs, do not remove in windy weather, and hypersensitive individuals should not attempt removal.