It’s a given that Humans work together as a society, and in nature many animal species do the same. Predators such as wolves hunt in packs to be more effective at bringing down large animals, which can supply enough food for all of the participants. But the most important reason animals stay in herds or flocks is protection from predators.
Hanging out in groups allows more eyes or noses to sense danger and sound the alarm. Members of a herd can scare off large predators by placing the young in the middle and defending the perimeter with spirited attacks. “Mobbing” is another method of group protection where prey species actively harass a nearby predator to the point that it departs. You may have seen this done by crows to a hawk. One other advantage to a grouping defense is the “confusion effect”, where so many prey animals moving at the same time distracts the predator and he misses the target.
Interesting names have been given to animal groups and here is a sampling of a few: A gaggle of geese; a school of fish; a flock of sheep; a herd of elephants; a plague of locusts; a colony of ants; a covey of quail; a kindle of kittens; a pod of seals; a sloth of bears; a rafter of turkeys; a flight of swallows; a clowder of cats; a descant of woodpeckers; a nest of rabbits; a fall of woodcocks; a skulk of foxes; a murmuration of starlings; a paddling of ducks; a drift of hogs; a siege of herons; a charm of finches; an unkindness of ravens; a shoal of bass; a drove of cattle; a labor of moles; a murder of crows; a cast of hawks; a knot of toads; a host of sparrows; a bale of turtles; a hover of trout; a parliament of owls.