Nutria
Myocaster coypus
These invaders of the Chesapeake's brackish
water marshes were introduced to the United States from South America in the 1930's.
They were introduced to supplement the fur trade after the Chesapeake's beaver
population was over-hunted. However, they are better known in the Chesapeake Bay
region for over-grazing and destroying wetland grass beds, thus contributing to
erosion problems.