Marine Introduced Species Q13: Are threats from marine invasive species increasing in Massachusetts and Cape Cod Bays?

Abstract

Non-native species have emerged as one of the leading environmental threats to our coastal habitats. These species have been recognized globally as a major threat to biological diversity as well as to agriculture and other human interests. Human activities such as shipping, aquaculture, and recreation, can result in the transfer of species from their native ranges to new areas. Non-native species, once introduced, have the potential to spread rapidly and become invasive, resulting in profound, adverse effects on marine systems and economies. Along the coast of Massachusetts and around the world, scientists have witnessed numerous invasions and subsequent impacts. While most foreign species are harmless, there are many examples of plants and animals that have caused ecological and/or economic problems when moved to new areas. As some introduced species become invasive, the physical conditions and habitats of native species ca be altered in a variety of ways that result in the exclusion of native species and favor those of the invader. Invasives can cause a decrease a decrease in native species populations, a decline in native species diversity, alteration of habitat, and changes in nutrient dynamics or productivity. Invasive species can also result in major economic impacts resulting from losses of important commercial resources and expenditures related to control and management (e.g. zebra mussels that clog intake pipes for water systems in the Great Lakes).