Squirrel monkeys play an important ecosystem role in Central and South America; they're an important part of the diet of some predators, and they control populations of insects by preying on them. Squirrel monkeys spend most of their time playing and foraging in the trees, but they sometimes head down to the ground. Although not considered endangered, squirrel monkey numbers are decreasing, due in part to human interference in their ecosystems.
Where They Live
Squirrel monkeys live in primary and secondary forests in countries such as Costa Rica, Brazil, Panama and Guyana. A primary forest is one filled with old growth, and a secondary forest is one recovering from devastation, such as from a fire or massive tree harvesting. Secondary forests are those still developing, meaning they typically don't have the same resources, such as mature trees and animal populations, as primary forests have. Squirrel monkeys aren't picky eaters, which helps them survive in a variety of forest locations.
What Eats Them
As part of a thriving ecosystem, squirrel monkeys aren't at the top of the food chain. Several animals rely on these monkeys for survival, hunting them out of trees or waiting for the monkeys to venture onto the ground. Harpy eagles and other raptors commonly hunt squirrel monkeys, as do snakes and large cats such as jaguars. In some countries, humans hunt squirrel monkeys for food as well.
What They Eat
Squirrel monkeys play a couple of important ecosystem roles in their forests. Their diets consist mostly of insects and fruit. Eating insects helps keep the pest population down. Since many of these insects feed on tree leaves, insect control gives the trees a better chance of survival. When the monkeys consume fruit, they pass the fruit seeds in their feces, helping spread the seeds along with some instant fertilizer. This is especially helpful in secondary forests that are still becoming established.
Dangers From Humans
Humans threaten the balance in squirrel monkeys' ecosystems. In addition to hunting the animals for food, some humans capture them to sell as pets or for scientific research purposes. The monkeys lose parts of their habitats as people cut down trees to expand towns or farms. When squirrel monkeys encounter electric power lines, they often climb on them and die from electrocution. Humans spraying insecticides in and around forested areas also kill squirrel monkeys. Declining squirrel monkey numbers, affect other ecosystem elements: Predators must find other food sources, insect populations can explode and tree seed will spread less effectively.
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