flocks
n. plural-onlyn. large groups of birds or sheep that stay together. You can also use it to describe a big crowd of people moving in the same direction.
n. large groups of animals, particularly birds or sheep, that congregate or travel together. Often used metaphorically to describe large crowds of people following a specific leader or trend.
Large flocks of birds fly south every winter.
The shepherd used his dogs to keep the flocks of sheep from wandering onto the main road.
As the sun began to set, massive flocks of starlings performed complex aerial displays across the horizon before settling in the reeds for the night.
While 'flock' is a countable noun, this plural form is frequently used to describe multiple distinct groups or a general abundance of animals.