Earthworms
DESCRIPTION:
Earthworms can vary in size, but the common night crawler is about six inches long, segmented, possesses barely visible hairs, and a smooth enlarged band about two inches from the front end. Night crawlers will mature in about one year and may live up to six years.
COMPOST JOB:
Earthworms are beneficial organisms for composting because they break down organic matter, their tunneling aerates the soil and reduces compaction.
Information courtesy of:
https://www.ces.ncsu.edu/depts/ent/notes/O&T/lawn/note125/note125.html