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Sea Turtles in the Dry Tortugas: Tracking Movements of Endangered Species in Florida's Coral-Reef Habitats

Kristen Hart and Keith Ludwig of the USGS Florida Integrated Science Center (FISC) participated in two research cruises in 2008 to study patterns of habitat use by endangered sea turtles in and around the National Park. Hart's research effort focuses on quantifying patterns of sea turtle habitat use, employing capture-recapture and satellite- and More...

  • One of the smallest juvenile green turtles (Chelonia agassizii) captured thus far, August 2008, Dry

Scleria lacustris (Wright's nut-rush) invasive and spreading in seasonal marshes of Florida

This web resource is a species profile and checklist for the Scleria lacustris (Wright's nut-rush), which is an invasive plant, which spreads in seasonal marshes of Florida. The site gives an introduction to the plant, along with identification tips with images of the weed.

  • Wright's nut-rush (Scleria lacustris)

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)

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

Asian shore crab, Japanese shore crab, Pacific crab, Hemigrapsus sanguineus (De Haan) (Arthropoda: Grapsidae)

This webpage is a species profile and nonindigenous species information bulletin of the Asian shore crab, Japanese shore crab, Pacific crab, Hemigrapsus sanguineus (De Haan)(Arthropoda: Grapsidae), with information on its identification and native range, life history, habitat, nonindigenous occurrences, means of introduction, its environmental More...

  • Asian Shore Crab (Hemigrapsus sanguineus)

Using Parasites to Monitor Ecosystem Health

Parasites can play a positive role in ecosystems. The USGS Western Ecological Research Center is working with the Channel Islands National Park in California to better understand how bacterial epidemics can protect kelp forests from overgrazing by sea urchins and how parasitic castrators might be used against invasive crabs. Researchers will More...

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Veined Rapa Whelk, Asian Rapa Whelk, Rapana venosa (Valenciennes, 1846) Mollusca: Gastropoda, Muricidae

This resource is a species profile and nonindigenous species information bulletin for the Veined Rapa Whelk, Asian Rapa Whelk, Rapana venosa (Valenciennes, 1846) Mollusca: Gastropoda, Muricidae. The shell is globose (rounded), with a very short-spire and large body whorl. The veined rapa whelks are carnivorous gastropods whose main diet More...

  • Veined Rapa Whelk, Rapana venosa (Actual size of specimen is ~6 in/152 mm)

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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