We have a small bachelor group of eastern pygmy marmosets.
They can be seen in the Small Monkey, Magic Forest exhibit.
Pygmy marmosets (Callithrix pygmaea nivieventris) are the smallest monkey in the world, and weigh about 6 oz. They are found in Brazil, Ecuador and Peru. Their habitat includes floodplain forest, which is close to rivers, the edges of agricultural fields, secondary growth forest, and also areas of bamboo.
A family group of pygmy marmosets is made up of an adult male and female, the main breeding pair, and offspring of varying ages. The group size can be as many as 15. The adult male and previous offspring carry the newborns, while the female does none of the parental care—she only has to feed them.
A group of pygmy marmosets have a territory which they patrol daily, and will defend it from other groups that happen to cross into it. They will do this with the whole group working together.
Their wild diet is mostly tree gum, and makes up about 60-70 percent of their diet. The bottom jaw of the pygmy marmoset is V-shaped to allow it to make holes in the tree bark. These holes let the tree’s gum flow out, and then the pygmies lick it up. A pygmy group will visit these trees throughout the day to eat the gum.
Other parts of the pygmy marmoset’s diet include fruit, insects, lizards, and spiders. During the dry season, when there are fewer insects and fruits around, nectar is very important to the pygmies. Pygmy marmosets forage for insects in small and medium-sized trees and in vine tangles. They rarely go down to the ground, but will do so to catch grasshoppers. Larger insects are a favourite food, as they have more protein in them and are worth the extra effort in catching. Pygmies jump on the insects to catch them. They can eat larger insects than would be expected for their small size!
Despite substantial habitat destruction occurring in some parts of its range, this does not seem to have affected pygmy marmoset populations. However, some populations in Colombia, may be impacted by collection for the pet trade.