After his first voyage to the Americas in 1492, Christopher Columbus took sweet potatoes back home to Europe. The crop was introduced into China in the late 16th century and spread through Asia, Africa, and Latin America during the 17th and 18th centuries.
North American river otters can live up to 21 years in captivity. They normally live about 8 to 9 years in the wild. North American river otters live alone or in family groups of, usually, females and their young. They are known as playful animals, often seen sliding in mud and snow and playing in the water.orth American river otters are semi-aquatic mammals, with long, streamlined bodies, thick tapered tails, and short legs. They have wide, rounded heads, small ears, and nostrils that can be closed underwater. Their whiskers are long and thick.
If fish populations start to decrease, river otters would lose their major food source, and their numbers will start to decline too. The river otter is also threatened by pollution of streams and rivers as well as the destruction of the vegetation on the banks of water bodies. Did You Know? River otters can hold their breath for up to 8 minutes underwater. River otters can dive to a depth of up to 60 feet. Otters always wash themselves after every meal. River otters spend two-thirds of their time on land.