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Explore WARC's science publications.

Filter Total Items: 3377

Temperature inverted haloclines provide winter warm-water refugia for manatees in southwest Florida

Florida manatees (Trichechus manatus latirostris) overwintering in the Ten Thousand Islands and western Everglades have no access to power plants or major artesian springs that provide warm-water refugia in other parts of Florida. Instead, hundreds of manatees aggregate at artificial canals, basins, and natural deep water sites that act as passive thermal refugia (PTR). Monitoring at two canal sit
Authors
Bradley Stith, James P. Reid, Catherine A. Langtimm, Eric D. Swain, Terry J. Doyle, Daniel H. Slone, Jeremy D. Decker, Lars E. Soderqvist

Modeling seasonal dynamics of small fish cohorts in fluctuating freshwater marsh landscapes

Small-bodied fishes constitute an important assemblage in many wetlands. In wetlands that dry periodically except for small permanent waterbodies, these fishes are quick to respond to change and can undergo large fluctuations in numbers and biomasses. An important aspect of landscapes that are mixtures of marsh and permanent waterbodies is that high rates of biomass production occur in the marshes
Authors
Fred Jopp, Donald L. DeAngelis, Joel C. Trexler

Salinity tolerance of the African Jewelfish Hemichromis letourneuxi, a non-native cichlid in South Florida (USA)

The African Jewelfish (Cichlidae: Hemichromis letourneuxi) is a predatory, non-native fish that has recently (since 2000) begun to expand its geographic range across south Florida. The salinity tolerance of H. letourneuxi was unknown, and thus it was unclear whether the species could use estuarine or coastal environments. The response of H. letourneuxi to chronic change in salinity was evaluated h
Authors
Jacqueline N. Langston, Pamela J. Schofield, Jeffrey E. Hill, William F. Loftus

Epizootic ulcerative syndrome caused by Aphanomyces invadans in captive bullseye snakehead Channa marulius collected from south Florida, USA

Epizootic ulcerative syndrome (EUS) caused by the oomycete Aphanomyces invadans is an invasive, opportunistic disease of both freshwater and estuarine fishes. Originally documented as the cause of mycotic granulomatosis of ornamental fishes in Japan and as the cause of EUS of fishes in southeast Asia and Australia, this pathogen is also present in estuaries and freshwater bodies of the Atlantic an
Authors
Ryan K. Saylor, Debra L. Miller, Mark W. Vandersea, Mark S. Bevelhimer, Pamela J. Schofield, Wayne A. Bennett

Reclaiming freshwater sustainability in the Cadillac Desert

Increasing human appropriation of freshwater resources presents a tangible limit to the sustainability of cities, agriculture, and ecosystems in the western United States. Marc Reisner tackles this theme in his 1986 classic Cadillac Desert: The American West and Its Disappearing Water. Reisner's analysis paints a portrait of region-wide hydrologic dysfunction in the western United States, suggesti
Authors
John L. Sabo, Tushar Sinha, Laura C. Bowling, Gerrit H.W. Schoups, Wesley W. Wallender, Michael E. Campana, Keith A. Cherkauer, Pam L. Fuller, William L. Graf, Jan W. Hopmans, John S. Kominoski, Carissa Taylor, Stanley W. Trimble, Robert H. Webb, Ellen E. Wohl

Detailed seafloor habitat mapping to enhance marine-resource management

Pictures of the seafloor capture important information about the sediments, exposed geologic features, submerged aquatic vegetation, and animals found in a given habitat. With the emergence of marine protected areas (MPAs) as a favored tactic for preserving coral reef resources, knowledge of essential habitat components is paramount to designing effective management strategies. Surprisingly, detai
Authors
David G. Zawada, Kristen M. Hart

Simultaneous modeling of habitat suitability, occupancy, and relative abundance: African elephants in Zimbabwe

The recent development of statistical models such as dynamic site occupancy models provides the opportunity to address fairly complex management and conservation problems with relatively simple models. However, surprisingly few empirical studies have simultaneously modeled habitat suitability and occupancy status of organisms over large landscapes for management purposes. Joint modeling of these c
Authors
Julien Martin, Simon Chamaille-Jammes, James D. Nichols, Herve Fritz, James E. Hines, Christopher J. Fonnesbeck, Darryl I. MacKenzie, Larissa L. Bailey

Satellite tracking reveals habitat use by juvenile green sea turtles Chelonia mydas in the Everglades, Florida, USA

We tracked the movements of 6 juvenile green sea turtles captured in coastal areas of southwest Florida within Everglades National Park (ENP) using satellite transmitters for periods of 27 to 62 d in 2007 and 2008 (mean ± SD: 47.7 ± 12.9 d). Turtles ranged in size from 33.4 to 67.5 cm straight carapace length (45.7 ± 12.9 cm) and 4.4 to 40.8 kg in mass (16.0 ± 13.8 kg). These data represent the fi
Authors
Kristen M. Hart, Ikuko Fujisaki

Physiological response of wild dugongs (Dugong dugon) to out-of-water sampling for health assessment

The dugong (Dugong dugon) is a vulnerable marine mammal with large populations living in urban Queensland waters. A mark-recapture program for wild dugongs has been ongoing in southern Queensland since 2001. This program has involved capture and in-water sampling of more than 700 dugongs where animals have been held at the water surface for 5 min to be gene-tagged, measured, and biopsied. In 2008,
Authors
Janet M. Lanyon, Helen L. Sneath, Trevor Long, Robert K. Bonde

Optimal control of native predators

We apply decision theory in a structured decision-making framework to evaluate how control of raccoons (Procyon lotor), a native predator, can promote the conservation of a declining population of American Oystercatchers (Haematopus palliatus) on the Outer Banks of North Carolina. Our management objective was to maintain Oystercatcher productivity above a level deemed necessary for population reco
Authors
Julien Martin, Allan F. O'Connell, William L. Kendall, Michael C. Runge, Theodore R. Simons, Arielle H. Waldstein, Shiloh A. Schulte, Sarah J. Converse, Graham W. Smith, Timothy Pinion, Michael Rikard, Elise F. Zipkin

Nutrient fluxes at the landscape level and the R* rule

Nutrient cycling in terrestrial ecosystems involves not only the vertical recycling of nutrients at specific locations in space, but also biologically driven horizontal fluxes between different areas of the landscape. This latter process can result in net accumulation of nutrients in some places and net losses in others. We examined the effects of such nutrient-concentrating fluxes on the R* rule,
Authors
Shu Ju, Donald L. DeAngelis