A group of moose is called a herd.
The word moose is both singular and plural. More than one moose is called moose, not "mooses." Moose is the North American name for what Europeans would call an elk or Alces alces. A male moose is a bull and a female is a cow. A baby moose is called a calf. A group of moose is called a herd of moose.
Although the proper name for a bunch of moose is a called a herd of moose, moose are solitary creatures that rarely gather together in groups. The Adirondack Educational Center notes that in the worst of winter when food is scarce, up to 15 moose will come quite close to each other and temporarily cooperate in tramping down and digging through snow to find food. This behavior is called "yarding up."
Most of the year, moose will stay by themselves, unless a mother is caring for her offspring. Calves stay with their mothers for one year, although they are weaned when they are five to six months old. Bulls and cows stay together for one or two days during the mating system. Sometimes bulls will try to mate with domestic cattle if they cannot find a fertile moose cow.
Do not approach a moose cow with calves. She is exceptionally protective and will charge. Bull moose can also charge anything that they perceive as a threat, including a human holding out food. Moose can reach speeds of 35 miles per hour. Leave moose alone or you may be seriously injured. Do not even approach a moose if you are in a car. Moose will charge the car.