The name “yapok†is derived from the Oyapock River in northern South America. Yapoks are found in Central and South America, from southern Mexico and Belize through all of Central America, and into Colombia, Venezuela, the Guianas, Ecuador, Peru, Paraguay, Brazil, and Northern Argentina. But in fact, the yapok is what you may know as water opossum.
Image source: BBC
Females are polyestrous, meaning that they come into heat and become receptive to mating more than once a year. A breeding pair stays together for several days, the male following and circling the female until actual mating. A typical litter contains one to five young.
Yapok young have the fastest rate of development among all the Didelphidae species. After about forty days in the pouch, the young have grown body fur, pigmentation and the various markings, and opened their eyes. At about fifty days, the young begin to let go of the nipples and leave the pouch, but continue to suckle and stay with the mother, sometimes riding on her back.
Individual water opossums are solitary and hostile toward others of their species, except during mating times. An individual hunts and forages in freshwater streams, between rest periods, throughout the night. During the day, the animal rests in a temporary ground nest that it constructs from leaves and grass in a shady area. Close by is a more permanent underground burrow, which the yapok excavates in the stream bank, with its entrance a few inches above the water line. The entrance tunnel is about 2 feet (0.6 meters) long, and leads to a den lined with leaves or grasses. Individuals use their prehensile tails to carry nesting materials.
A yapok fishes and forages underwater, propelling itself with alternate strokes of its powerful hind legs and webbed feet. The animal shuts its eyes and ears and depends partly on its whiskers to detect motion, while its fingers, acutely sensitive to touch, are used to contact, check the texture of, and grasp prey.
The longest known lifespan for a captive yapok is three years.
Water opossums, confined to forests and riversides by their specialized lifestyles, are no threat or bother to humanity. Humans hunt them for their waterproof pelts, to be made into garments and accessories.