Notes

Asian carp —a catchall title for species of silver, bighead and
black carp from Asia—are a fast-
growing fish that out-compete
native fish for food and habitat.
Brown marmorated stink bugs have become an increasing nuisance in homes and to the agriculture industry. Away from
their natural predators, stink
bug populations are expanding
rapidly.
West Nile virus, spread by mosquitoes infected with the virus, is an invasive pathogen that has caused direct harm to humans (sometimes resulting in death) as well as to wildlife (especially birds). It has been detected throughout most of the continental United States.
Cogongrass is an Asian plant that arrived in the U.S. as seeds in packing material. It is now spreading through the Southeast, displacing native plants.  It provides no food value for native wildlife, and increases the threat of wildfire as it burns hotter and faster than native grasses.
Feral pigs will eat almost anything, including native birds. They compete with native wildlife for food sources such as acorns. Feral pigs spread diseases, such as brucellosis, to people and livestock.  E. coli from their feces was implicated in the E. coli contamination of baby spinach in 2006.
Zebra mussels first came to the U.S. from Eurasia in ship ballast water released into the Great Lakes. Since 1988, they have spread dramatically, out-competing native species for food and habitat. Zebra mussels can attach to almost any hard surface - they clog water intake and discharge pipes, attach themselves to boat hulls and docks, and they even attach to native mussels and crayfish.
European green crabs found their way into the San Francisco Bay area in 1989. They out-compete native species for food and habitat and eat huge quantities of native shellfish, threatening commercial fisheries.
Dutch elm disease (caused by the fungus Ophiostoma ulmi) is transmitted to trees by elm bark beetles. Since 1930, the disease has spread from Ohio through most of the country, killing over half of the elm trees in the northern U.S.
Water hyacinth is a beautiful aquatic plant, introduced to the U.S. from South America as an ornamental. In the wild, it forms dense mats, reducing sunlight for submerged plants and aquatic organisms, crowding out native aquatic plants and clogging waterways and intake pipes.