The Science of Sustainability
2.3 Human Activity Impacts on Ecosystems
Invasive Species
Invasive species are brought on by transporting species either intentionally or accidentally from other areas of the world. This can be devastating to existing species as invasive species are introduced on a timescale much more quickly than typically would happen with evolution over longer time periods. This can include outcompeting native species in the ecosystem, leading to the decline or extinction of local species, and overpopulation as these invasive species may not have any predators in this new ecosystem. They also can be a major economic cost.
Figure 2.7 Invasive Species the Zebra Mussel
The zebra mussel provides an invasive species that has had significant economic impacts. The zebra mussel is native to lakes in Russia but was accidentally introduced in the United States and Canada through the ballast water of commercial ships that were transporting goods to the Great Lakes region in the 1980s. They have been spreading ever since and have recently been found in lakes in Massachusetts; they attach to recreational boats and are transported wherever the boat may go. They colonize rapidly and have covered the undersides of docks, boats, and other marine structures and can grow so thick that they block municipal water and hydroelectric pipelines. The cost of pest management for zebra mussels at power plants and other water-consuming facilities is approximately $500 million a year in the United States.