The Squirrel Monkey is the most abundant monkey in the Amazon Rainforest. Squirrel Monkeys stick together in groups of around twenty to one hundred. These monkeys are often found near large bodies of water. Adult squirrel monkeys weigh anywhere from five hundred to one thousand grams. The diet of this monkey consists of fruits, insects, and sometimes flower nectar. The squirrel monkey is active both at night and during the day.

Although most of the water the squirrel monkey needs is obtained from the food it eats, they also obtain water by drinking it from holes in trees or puddles on the ground.