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Long Term Resource Monitoring Program

This web resource provides decision makers with the information needed to maintain the Upper Mississippi River System as a viable multiple-use large river ecosystem. This resource also includes Data and sampling information, publication links, reports, other related documents and statistics, as well as links to field stations and other projects More...

  • hoop net

Foreign Nonindigenous Carps and Minnows (Cyprinidae) in the United States - A Guide to their Identification, Distribution, and Biology

This guide contains an identification key to the eleven foreign nonindigenous cyprinids, as well as species accounts that include physical characteristics, reproduction, ecology, and distribution in its native habitat and in the United States. Biologists, resource managers and others interested in nonindigenous fishes will find it a useful tool More...

  • Carp ID Cover Image

Nonindigenous Fish Program

New nonindigenous fishes are introduced to the region's waters each year and already-established invasive fishes continually expand their ranges. Assessing the effects of a new invader on native species and environments is complicated by the fact that most habitats are under stress as a result of human disturbance and because many sites are More...

  • Spotted Tilapia (Tilapia mariae)

Case of the Red Shiner: What Happens When a Fish Goes Bad?

The red shiner (Cyprinella lutrensis) is a hardy, widespread minnow native to the middle and southwestern United States and Mexico. Its native range encompasses the lowland tributaries of the Mississippi River and western Gulf slope drainages to the Rio Grande River. The red shiner peripherally occurs in the southeastern United States, inhabiting More...

  • Male red shiner in near-peak spawning coloration (46 mm Standard Length).

Asian Carp Invasion of the Upper Mississippi River System

The Long Term Resource Monitoring Program (LTRMP) has been collecting Asian carp from the Upper Mississippi River System (UMRS) and documenting changes in abundance and size structure. This research summary shows the annual increase in number of catches since 1990 and compares habitat type and collecting gear types to the percentage of catches.

  • Upper Mississippi River System and locations of Long Term Resource Monitoring Program trend analysis

Eurasian Ruffe

Eurasian Ruffe pose a threat to native fish because they(1) mature quickly, (2) have a high reproductive capacity, and (3) easily adapt to new environments. Ruffe were first detected in western Lake Superior in 1986. UMESC scientists are conducting research on various types of piscicides (chemicals that kill fish). They are attempting to develop More...

  • Eurasian ruffe (Gymnocephalus cernuus)

Low-temperature tolerance of African jewelfish, (Hemichromis letourneuxi)

Because the African jewelfish has a broad salinity tolerance, scientists tested how the species low-temperature tolerance varied at three salinities: freshwater (0 ppt), brackish (10 ppt) and marine (35 ppt) in the laboratory. A field experiment was then conducted to examine the survivorship of individuals when caged in several common aquatic More...

  • Image of an African jewelfish, (Hemichromis letourneuxi)

Building Experimental Capacity to Assess Ballast Treatment Effectiveness and Residual Risk

Ballast water discharges are the most significant cause of aquatic biological invasions in coastal waters, including the Great Lakes. Currently, treatment of ballast water prior to discharge at the receiving port offers significant promise to help control this problem. However, development of treatment technologies is limited by lack of objective More...

  • Image of ship discharging ballast water

Understanding Everglades Invaders: Ecophysiology of the African Jewelfish (Hemichromis letourneuxi)

A dozen species of non-indigenous fishes have colonized the wetlands of south Florida. Information relating to their biology, ecology, and environmental tolerances has been accumulating, but data gaps remain for several common species. These data are needed to understand and model the ultimate range expansion, habitat occupation and dynamics of More...

  • African jewelfish (Hemichromis letourneuxi)

Salinity Tolerance of Hemichromis letourneuxi

The African jewelfish (Hemichromis letourneuxi) has been established in canals surrounding the Miami area since the 1960s. With changes in water delivery to the park, the species has recently (2000) entered Everglades National Park and expanded its range westward through Big Cypress National Preserve. Simultaneously, African jewelfish from a More...

  • African jewelfish (Hemichromis letourneuxi)

Effects of salinity on survival, growth and reproduction of non-native Nile tilapia (Oreochromis niloticus) from southern Mississippi

The Nile tilapia (Oreochromis niloticus) is commonly used in aquaculture worldwide. Feral populations exist in many regions where individuals escape culture and establish in natural habitats. In Mississippi, Nile tilapia are established in at least three distinct localities (fig. 1): the lower Pascagoula and Escatawpa river drainages, and a More...

  • Image of Nile tilapia (Oreochromis niloticus)

Snakeheads (Pisces, Channidae) - A Biological Synopsis and Risk Assessment

Snakeheads (family Channidae) are airbreathing freshwater fishes containing two genera, Channa with 26 species native to Asia, Malaysia, and Indonesia; and Parachanna with 3 species native to tropical Africa. Some snakeheads are small, reaching about 17 centimeters, but most are much larger, the largest reported to be 1.8 meters in length. All are More...

  • cover of Snakeheads publication