Answer:

herds

Answer	Crossword Clue
HERDS	Packs of alpacas
HERDS	They're rounded up in roundups
HERDS	Drives in a field

HERDS	Groups of bison
HERDS	Does a sheepdog's job
HERDS	Rounded-up numbers?
HERDS	Range rovers
HERDS	Groups of buffalo
HERDS	Ranch stock
HERDS	Wrangles
HERDS	Grazing groups

HERDS	Elephant groups
HERDS	Gathers
HERDS	Zebra groups
HERDS	Cattle groups