Invasive Species…..What are they and why are they a problem?
The spread of invasive species is recognized as one of the major factors contributing to ecosystem change and instability throughout the world.  An invasive species is “a non-native species whose introduction does, or is likely to cause, economic or environmental harm or harm to human, animal, or plant health” (Executive Order 13112, 1999). Invasive species include all taxa of organisms, ranging from microscopic insects to 100 lb sheep, and can invade any ecosystem, from river beds to lava fields. These species have the ability to displace or eradicate native species, alter fire regimes, damage infrastructure, and threaten human livelihoods. Invasive species are changing the iconic landscapes of our National Parks. 

Quick facts on invasive species in National Parks

• Over 6,500 non-native invasive species have been documented on park lands
• 70% of documented invasive species on park lands are invasive plant species
• Around 5% of park lands are dominated by invasive plants
• More than 650 invasive species have been found in marine parks (approximately 10% of all invasive species found in national parks occur in marine environments.)

Invasive Species Management on NPS Lands
The National Park Service is working to manage invasive species on park lands through a suite of national and local programs, each based upon the following strategies: cooperation and collaboration, inventory and monitoring, prevention, early detection and rapid response, treatment and control, and restoration.  Click on each strategy to learn more.  At the national level, NPS has fostered a successful invasive plant management program with the creation of the Exotic Plant Management Teams (EPMT).  These 16 teams provide highly trained mobile assistance in invasive plant management to parks throughout the National Park System.  To learn more about the teams, click here.  Almost all parks have incorporated invasive species management into long range planning goals for natural and cultural landscapes, as well as day to day operations.  For example, Curecanti and Glen Canyon National Recreation Areas have implemented “boat checks” to help visitors make sure their boats are free of zebra and quagga mussels prior to entering the park. To learn more about invasive species in marine parks, click here.

Invasive Species of the Month: Quagga Mussel – Dreissena burgensis

Native to Eastern Europe, these mussels have invaded waterways throughout the United States.  Most recently the Quagga mussels have been moving westward and were identified in Lake Mead.  These mussels have several significant impacts on the water bodies they invade.  The Quagga deplete the plankton levels, reducing food supply for native aquatic organisms.  Quagga also attach to and damage infrastructure such as water intake pipes, docks, and boats.  Help prevent the spread of Quagga by cleaning your equipment and gear prior to leaving a site.  To learn more about these mussels, click here. To learn how to properly clean your gear, click here.