Last updated on Thursday, September 29, 2011 http://water.epa.gov/type/oceb/hab itat/invas ive_species_index.cfm 

## Water: Habitat Protection

You are here: Water Our Waters Oceans, Coasts, Estuaries & Beaches Habitat Protection Invasive Species 

# Invasive Species

Invasive species means an alien species whose intro duction does or is likel y to cause economic or environmental harm or harm to human health. Invasive species are one of the largest threats to our terrestrial, coastal and freshwater ecosystems, as well as being a major global concern. Invasive species can affect aquatic ecosystems directly or by affecting the land in ways that harm aquatic ecosystems. Invasive species represent the second leading cause of species extinction and loss of biodiversity in aquatic environments worldwide. They also result in considerable economic effects through direct economic losses and management/control costs, while dramatically altering ecosystems supporting commercial and recreational activities. E ffects on aquatic ecosystems result in decreased native populations, modified water tables, changes in run-off dynamics and fire frequency, among other alterations. These ecological changes in turn impact many recreational and commercial activities dependent on aquatic ecosystems. Common sources of aquatic invasive species introduction include ballast water, hull fouling, aquaculture escapes, and accidental and/or intentional introductions, among
others.

 Pathways for Species Introduction

 Useful Links to Invasive Species Information



### Vessels and Invasive Species

Vessels can be a significant pathway for the introduction or spread of invasive species through the discharge of ballast water containing invasive species or the transport of invasive species that have accumulated as biofouling on ships' hulls. EPA and its federal partners, such as the U.S. Coast Guard, are working together and using their authorities to helpaddress the environmental and economic threats associated with shiprelated introductions of invasive species. For info rmation on EPA activities under the Clean Water Act addressing this issue visit the EPA Vessel Discharges , and EPA Clean Boating Act webpages. For information on U.S. Coast Guard activities under their statutory authorities, visit the U.S. Coast Guard Aquatic Nuisance Species webpage.



### Oceans, Coasts, Estuaries & Beaches Quick Finder

Oceans, Coasts, & Estuaries Home Coastal Watershed Protection Marine Pollution Prevention Monitoring and Assessment Ocean & Coastal Partnerships Frequently Asked Questions Coasts for Kids

You will need Adobe Reader to view some of the files on this page. See EPA's PDF page to learn more. Features

Overview of EPA Authorities for Natural Resource Managers Developing Aquatic Invasive Species Rapid Response and Management Plans
Economic Impacts of Aquatic Invasive Species Workshop
Executive Order 13112 on Invasive Species (PDF) (4 pp, 68 KB)

Ecological and Economic Impacts and Invasion Management Strategies for the European Green Crab (PDF) (73 pp, 826 KB)
Watershed Academy Web: Invasive Non

Native Species Purple Loosestrife. This beautiful plant is highly aggressive in the wild, displacing native vegetation.

Corbicula fluminea. Often called the Asian clam, this small mollusk can clog intake pipes for cooling water. 

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