What are aquatic nuisance species?

Aquatic nuisance species (ANS) refer to non-native or invasive species that have been introduced into aquatic ecosystems outside their natural range and pose significant economic, ecological, and human health risks. These species can adversely affect native biodiversity, ecological balance, water quality, fisheries, infrastructure, recreation, and even human health.

Examples of well-known ANS include:

1. Zebra Mussels (Dreissena polymorpha): These freshwater mussels have caused substantial ecological and economic impacts in North America. They multiply rapidly, forming dense colonies that can clog water intake pipes, damage boat hulls, alter food webs, and harm native mussels.

2. Eurasian Watermilfoil (Myriophyllum spicatum): An invasive aquatic plant that outcompetes native plants for resources, blocks sunlight from reaching underwater plants, impedes water flow, interferes with recreation, and provides shelter for non-native species.

3. Asian Carp (Hypophthalmichthys spp.): This group of four fish species (bighead carp, grass carp, silver carp, and black carp) were introduced to manage aquatic plants and algae in ponds and aquaculture facilities. However, their proliferation in rivers and lakes has led to significant alterations in fish communities and competition with native species for food resources.

4. Quagga Mussels (Dreissena bugensis): Similar to zebra mussels, quagga mussels rapidly colonize hard surfaces and have severe impacts on aquatic ecosystems, including affecting water clarity, damaging infrastructure, and interfering with native species.

To address the spread and mitigate the impacts of ANS, various measures are often employed, including public education, border control and inspection, early detection and rapid response, ballast water management regulations, and restrictions on the release of pets and unwanted aquarium species into natural water bodies.