Species not Established in the U.S.

The following species of concern provides examples of why we must increase our efforts in early detection and rapid response and prevention of new introductions. See Manager's Tool Kit - Early Detection and Rapid Response: Species not Established in the U.S. for general resources and other species information.

• Nile perch
• Golden mussel
• Killer shrimp
• Oxygen weed

This information is provided as an educational tool and is not inclusive of all invasive aquatic species not yet established in the U.S.

Scientific name: Lates niloticus                     

Common name: Nile Perch

Native To: Africa (Schofield 2011)

Date of U.S. Introduction: August 1975 (Rutledge and Lyons 1976)

Means of Introduction: Intentionally introduced to Texas for sport fishing (Rutledge and Lyons 1976)

Images: Google

Impact: Was introduced to Lake Victoria (Africa) in 1954, where it destroyed 200 native species of fish through predation and competition for food (Kaufman 1992); no negative impact in Texas so far as the species is still controlled (Schofield 2011)

Resources:
Lates niloticus - Nonindigenous Aquatic Species Database
DOI. Florida Integrated Science Center. Center for Aquatic Resource Studies.

Lates niloticus (fish) - ISSG Global Invasive Species Database
World Conservation Union. Invasive Species Specialist Group.

Scientific name: Limnoperna fortunei (Dunker, 1857)

Common name: Golden mussel

Native To: China and South Eastern Asian rivers and creeks

Date of U.S. Introduction: n/a

Images: Google

Means of Introduction: Has invaded South America through ballast water, and could be introduced to North America through ballast water (Global Invasive Species Database 2005)

Impact: Threatens native biodiversity, suffocate and starve out native bivalves and produce macrofouling in water systems (Global Invasive Species Database 2005)

Resources:
Limnoperna fortunei (mollusc) – ISSG Global Invasive Species Database
World Conservation Union. Invasive Species Specialist Group.

Golden mussel - Limnoperna fortunei (PDF | 640 KB)
DOD. USACE. Engineer Research and Development Center. Environmental Laboratory.

Scientific name: Dikerogammarus villosus (Sowinsky, 1894)

Common name: Killer shrimp

Native To: Eastern Europe (Crosier et al. 2006)

Date of U.S. Introduction: n/a

Images: Google

Means of Introduction: In Europe, most likely through ballast water and could enter the U.S. in the same way (Crosier et al. 2006)

Impact: In Europe killer shrimp populations have caused significant ecological disruption, including reduced biodiversity and local species extinction (Crosier et al. 2006)

Resources:
Killer shrimp - Dikerogammarus villosus (PDF | 209 KB)
DOD. USACE. Engineer Research and Development Center. Environmental Laboratory.

Scientific name: Lagarosiphon major (Ridley) Moss

Common name: Oxygen weed

Native To: Southern Africa (McGregor and Gourlay 2002)

Date of U.S. Introduction: n/a

Means of Introduction: Spread throughout the world as an aquarium plant (National Heritage Trust 2003)

Images: Invasive.org and Google

Impact: Has invaded New Zealand and Europe. It can inhabit freshwater lakes, dams and slow moving streams. Forms dense mats that block sunlight, thereby killing native aquatic plant and animal species, which could rival the harmful effects of hydrilla. (Csurhes and Edwards 1998)

Resources:
Lagarosiphon major - Non-Native Invasive Aquatic Plants in the United States
University of Florida. Center for Aquatic and Invasive Plants.

Lagarosiphon major (aquatic plant) - ISSG Global Invasive Species Database
World Conservation Union. Invasive Species Specialist Group.

Citations

Crosier, D.M. D.P. Molloy, A. bij de Vaate, and S. Devin. 2006. Killer Shrimp - Dikerogammarus villosus (PDF | 209 KB). U.S. Department of Defense. USACE. Engineer Research and Development Center. Environmental Laboratory.

Csurhes, S. and R. Edwards. 1998. Potential environmental weeds in Australia: Candidate species for preventative control (PDF | 1.3 MB). Canberra, Australia. Biodiversity Group, Environment Australia. 208 pp.

Global Invasive Species Database. 2005. Limnoperna fortunei (mollusc). Invasive Species Specialist Group (ISSG) of the IUCN Species Survival Commission.

Kaufman, L.  1992. Catastrophic change in species-rich freshwater ecosystems: the lessons of Lake Victoria.  Bioscience 42: 846-858.

McGregor, P.G. and H. Gourlay, 2002. Assessing the prospects for biological control of lagarosiphon (Lagarosiphon major (Hydrocharitaceae) (PDF | 109 KB). Department of Conservation. Wellington, New Zealand.

National Heritage Trust. 2003. Lagarosiphon - Lagarosiphon major. Weed Management Guide.

Rutledge, W.P. and B.W. Lyons. 1976. Texas peacock bass and Nile perch: status report (PDF | 396 KB). Thirtieth Annual Conference, Southeastern Association of Game and Fish Commissioners.

Schofield, P.J.. 2011. Lates niloticus. USGS Nonindigenous Aquatic Species Database, Gainesville, FL.