Here we have the cluster caterpillars just hatching, so many of them at once so no wonder the do lots of damage.
Caterpillars are the larvae of moths and butterflies which are usually out and about through summer and autumn. They are pests because they eat the leaves of crop plants. You really don’t need to know exactly what type of caterpillar is feeding on your plants as all of them do the same damage.
There are a number of related species that are found in the garden including armywork, earworm, Helicoverpa, Heliothis, loopers, cutworm and the cluster caterpillar as shown in this video.