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Explore WARC's science publications.

Filter Total Items: 3374

Manatee grazing impacts on a mixed species seagrass bed

The endangered manatee Trichechus manatus is one of few large grazers in seagrass systems. To assess the long-term impacts of repeated grazing on seagrasses, we selected a study site within Kennedy Space Center in the northern Banana River, Brevard County, Florida, that was typically grazed by large numbers of manatees in spring. Two 13x13 m manatee exclosures and 2 paired open plots of equal size
Authors
Lynn W. Lefebvre, Jane A. Provancha, Daniel H. Slone, W. Judson Kenworthy

Conservation genetics of American crocodile, Crocodylus acutus, populations in Pacific Costa Rica

Maintaining genetic diversity is crucial for the survival and management of threatened and endangered species. In this study, we analyzed genetic diversity and population genetic structure at neutral loci in American crocodiles, Crocodylus acutus, from several areas (Parque Nacional Marino Las Baulas, Parque Nacional Santa Rosa, Parque Nacional Palo Verde, Rio Tarcoles, and Osa Conservation Area)
Authors
Laurie A. Mauger, Elizabeth Velez, Michael S. Cherkiss, Matthew L. Brien, Frank J. Mazzotti, James R. Spotila

Demersal fish assemblages on seamounts and other rugged features in the northeastern Caribbean

Recent investigations of demersal fish communities in deepwater (>50 m) habitats have considerably increased our knowledge of the factors that influence the assemblage structure of fishes across mesophotic to deep-sea depths. While different habitat types influence deepwater fish distribution, whether different types of rugged seafloor features provide functionally equivalent habitat for fishes is
Authors
Andrea M. Quattrini, Amanda W.J. Demopoulos, Randal Singer, Adela Roa-Varon, Jason D. Chaytor

Numerical modeling of the effects of Hurricane Sandy and potential future hurricanes on spatial patterns of salt marsh morphology in Jamaica Bay, New York City

The salt marshes of Jamaica Bay, managed by the New York City Department of Parks & Recreation and the Gateway National Recreation Area of the National Park Service, serve as a recreational outlet for New York City residents, mitigate flooding, and provide habitat for critical wildlife species. Hurricanes and extra-tropical storms have been recognized as one of the critical drivers of coastal wetl
Authors
Hongqing Wang, Q. Chen, Kelin Hu, Gregg A. Snedden, Ellen K. Hartig, Brady R. Couvillion, Cody L. Johnson, Philip M. Orton

Relationships between salinity and short-term soil carbon accumulation rates form marsh types across a landscape in the Mississippi River Delta

Salinity alterations will likely change the plant and environmental characteristics in coastal marshes thereby influencing soil carbon accumulation rates. Coastal Louisiana marshes have been historically classified as fresh, intermediate, brackish, or saline based on resident plant community and position along a salinity gradient. Short-term total carbon accumulation rates were assessed by collect
Authors
Melissa M. Baustian, Camille L. Stagg, Carey L. Perry, Leland C Moss, Tim J. B. Carruthers, Mead Allison

Expert elicitation, uncertainty, and the value of information in controlling invasive species

We illustrate the utility of expert elicitation, explicit recognition of uncertainty, and the value of information for directing management and research efforts for invasive species, using tegu lizards (Salvator merianae) in southern Florida as a case study. We posited a post-birth pulse, matrix model in which four age classes of tegus are recognized: hatchlings, 1 year-old, 2 year-olds, and 3 + y
Authors
Fred A. Johnson, Brian J. Smith, Mathieu Bonneau, Julien Martin, Christina Romagosa, Frank J. Mazzotti, J. Hardin Waddle, Robert Reed, Jennifer Kettevrlin Eckles, Laurie J. Vitt

Predicting the impacts of Mississippi River diversions and sea-level rise on spatial patterns of eastern oyster growth rate and production

There remains much debate regarding the perceived tradeoffs of using freshwater and sediment diversions for coastal restoration in terms of balancing the need for wetland restoration versus preserving eastern oyster (Crassostrea virginica) production. Further complicating the issue, climate change-induced sea-level rise (SLR) and land subsidence are also expected to affect estuarine water quality.
Authors
Hongqing Wang, Q. Chen, Megan La Peyre, Kelin Hu, Jerome F. La Peyre

Operational shoreline mapping with high spatial resolution radar and geographic processing

A comprehensive mapping technology was developed utilizing standard image processing and available GIS procedures to automate shoreline identification and mapping from 2 m synthetic aperture radar (SAR) HH amplitude data. The development used four NASA Uninhabited Aerial Vehicle SAR (UAVSAR) data collections between summer 2009 and 2012 and a fall 2012 collection of wetlands dominantly fronted by
Authors
Amina Rangoonwala, Cathleen E Jones, Zhaohui Chi, Elijah W. Ramsey

The significant surface-water connectivity of "geographically isolated wetlands"

We evaluated the current literature, coupled with our collective research expertise, on surface-water connectivity of wetlands considered to be “geographically isolated” (sensu Tiner Wetlands 23:494–516, 2003a) to critically assess the scientific foundation of grouping wetlands based on the singular condition of being surrounded by uplands. The most recent research on wetlands considered to be “ge
Authors
Aram J.K. Calhoun, David M. Mushet, Laurie C. Alexander, Edward S. DeKeyser, Laurie Fowler, Charles R. Lane, Megan W. Lang, Mark C. Rains, Stephen Richter, Susan C. Walls

Structured decision making as a conservation tool for recovery planning of two endangered salamanders

At least one-third of all amphibian species face the threat of extinction, and current amphibian extinction rates are four orders of magnitude greater than background rates. Preventing extirpation often requires both ex situ (i.e., conservation breeding programs) and in situ strategies (i.e., protecting natural habitats). Flatwoods salamanders (Ambystoma bishopi and A. cingulatum) are protected un
Authors
Katy O'Donnell, Arianne F Messerman, William J. Barichivich, Raymond D. Semlitsch, Thomas A. Gorman, Harold G Mitchell, Nathan Allan, Dante B. Fenolio, Adam Green, Fred A. Johnson, Allison Keever, Mark Mandica, Julien Martin, Jana Mott, Terry Peacock, Joseph Reinman, Stephanie S. Romañach, Greg Titus, Conor P. McGowan, Susan C. Walls

Taxonomic revision of the South American catfish genus Ageneiosus (Siluriformes: Auchenipteridae) with the description of four new species

The catfish genus Ageneiosus in the exclusively Neotropical family Auchenipteridae is revised. Species of Ageneiosus are widely distributed in all major South American continental drainages except the São Francisco River basin and small rivers along the Brazilian east coast. The taxonomic revision was based on examination of available type specimens, additional museum material and comparisons of o
Authors
Frank R.V. Ribeiro, Lúcia H. Rapp Py-Daniel, Stephen J. Walsh