Coots are omnivorous, eating mainly plant material, but also small animals and eggs. They are aggressively territorial during the breeding season, but are otherwise often found in sizeable flocks on the shallow vegetated lakes they prefer.
At least some coots have difficulty feeding a large family of hatchlings on the tiny shrimp and insects that they collect. So after about three days they start attacking their own chicks when they beg for food. After a short while, these attacks concentrate on the weaker chicks, who eventually give up begging and die. The coot may eventually raise only two or three out of nine hatchlings. In this attacking behaviour, the parents are said to `tousle` their young. This can result in the death of the chick.
A group of coots may be referred to as a covert or cover.