What is an invasive species? An invasive species is an animal or
plant that did not evolve in the Chesapeake Bay region and that
has a negative effect on the Bay’s ecosystem. Invasive species
arrive in Maryland through various means, including through the
ballast of ships, in the packing material of imported goods, and
through deliberate import. Not all non-native species are
invasive and some that initially seemed benign or beneficial -
such as grass carp or European starlings - develop invasive
characteristics long after their arrival. The Maryland
Department of Natural Resources has identified more than 200
non-native species that may be invasive, including nutria, a
large South American rodent; mute swans; zebra mussels; water
chestnut; and wavyleaf basketgrass. Such species are able to
thrive, in part, because their “new” environment lacks natural
ecological controls such as predators and disease, found in
native habitats. Once established, invasive species can be very
difficult and costly to eradicate o