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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).

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)

Zebra Mussels

Zebra mussels have caused drastic declines in native clam and mussel populations in some locations. Zebra mussels compete with other invertebrates and young fish for plankton, the primary food source for these groups. UMESC scientists are investigating the effects zebra mussels are having on the riverine ecosystem. This study examines the effects More...

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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

FrogWeb: Amphibian Declines

A web resource for research in amphibian declines phenomena, habitat loss, climate change by exposure to UV radiation, contaminants and pollutants, disease, and predation by invasive species. General resources relating to declines phenomena and monitoring tools and resources are available on this webpage.

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Influence of Timber Harvest and Floods on the Distribution of Exotic Riparian Plants

Riparian vegetation is intimately linked to the stream and river channels along which it grows. This project addresses the status of the riparian zone along Redwood Creek north coastal California, and answers three questions: 1) How have the overstory riparian conditions changed in Redwood Creek and major tributaries since the advent of timber More...

  • Scotch Broom (Cytisus scoparius) colonizes bare ground areas

National Resources Monitoring Partnership (NRMP)

Natural resource managers face complex decisions that require a clear understanding of the status of wildlife populations and their habitats. Monitoring is key to making effective management decisions and evaluating the outcomes of those decisions. The goal of NRMP is to improve the accessibility of monitoring efforts to resource managers to aid More...

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National Resources Monitoring Partnership (NRMP) Newsletter

Natural Resource Monitoring Partnership (NRMP) is a collaborative effort by the natural resource management community to improve monitoring efforts in order to support effective evaluation and decision-making by sharing information on monitoring projects and protocols. The Natural Resource Monitoring Partnership was built for easy access to More...

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Role of Demographic, Genetic, and Environmental Factors Influencing the Spread of Hybridization Between Native Westslope Cutthroat and Non-Native Rainbow Trout

This research project examines dispersal and several components of fitness between hybrids and non-hybridized fish. Further, scientists will examine the relationship between environmental factors and genetic and demographic characteristics of hybrid populations. The specific objectives are: (1) to compare the spawning dynamics and dispersal More...

  • Radiotagged hybrid trout

Zebra and Quagga Mussel Distribution in U.S. Lakes

This web resource is a map representation of the distribution of zebra and quagga mussels in U.S. lakes. Zebra mussels were first detected in 1988 in Lake St. Clair, located between Lake Huron and Lake Erie. Within just a few years, they spread into all five of the Great Lakes. Since then, zebra mussels have spread into many large navigable More...

  • Image of a zebra mussel (Dreissena polymorpha)