Burmese pythons can grow to be one of the five largest snakes in the world and are currently wreaking havoc in the Everglades, preying upon native species and disrupting the ecosystem. Burmese pythons were originally introduced through the pet trades, so it is important that pet owners secure snakes and do not release them in the wild.

Emerald ash borer infestations can devastate urban and natural forests in a very short time period by cutting off nutrient supplies. The emerald ash borer is already established in the northeastern U.S. and its distribution is moving across the Midwest. Closely monitoring firewood movement in quarantined areas is essential to controlling its spread.

Feral pigs can cause severe damage to crops, forests, and rangelands through their intensive rooting behavior. Feral pigs are found across the southeastern U.S. and California and their spread is attributed to free-ranging practices that persisted until the mid-20th century. Electric or strong mesh fencing may be a way to reduce further damage to property.

Hydrilla is considered one of the most problematic species of aquatic plants to both fish and wildlife habitat and to recreation. Areas most affected include the southeastern U.S. and several West Coast states. Boaters should take care to clean hydrilla off vessels, especially if they plan to travel between water bodies.

Japanese knotweed is a terrestrial plant that quickly crowds out native species, especially near lakes and streams. Originally introduced as an ornamental, the Japanese knotweed now occupies areas within the eastern U.S. and the Midwest. Gardeners should be familiar with invasive plant species and request only non-invasive plants from nurseries and garden centers.

Silver carps out-compete native fish populations for resources and will likely overwhelm a profitable fishing industry if allowed into the Great Lakes. Currently, silver carps are found in the Mississippi River and its major tributaries as far north as Minnesota. Promoting silver carp as a food source may be a measure to prevent its future spread.

Zebra mussels are small freshwater mussels that attach to virtually any hard surface and pervade the Great Lakes and Mississippi River basins and some small lakes in the southwestern U.S. They cause both economic and ecological harm and cost millions of dollars annually to control. It is important for recreational boaters to keep their boats clean to prevent further spread of this species.