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Publications

Explore WARC's science publications.

Filter Total Items: 3374

Cumulative spring discharge and survey effort influence occupancy and detection of a threatened freshwater mussel, the Suwannee Moccasinshell

Freshwater mussels (Unionidae) are among the most imperiled groups of organisms in the world, and the lack of information regarding species distributions, life-history characteristics, and ecological and biological requirements may limit the protection of remaining mussel populations. We examined the influence of hydrologic factors on the occurrence of the Suwannee Moccasinshell Medionidus walkeri
Authors
Jordan M. Holcomb, Colin P. Shea, Nathan A. Johnson

President elect's message

The first morning home the day after I became president of SWS at the annual meeting in Denver, I note the wilting of my garden and the grumpiness of my cats as the dawn of my new reality. The extra hours that I will spend as president of SWS will manifest itself as more cat and garden unhappiness as travel and responsibilities grow. The cats gleefully blast out of the door into the backyard, beca
Authors
Beth A. Middleton

Ecological resilience indicators for salt marsh ecosystems

Salt marshes are coastal ecosystems within the intertidal zone, characterized by hypoxic, saline, soil conditions and low biodiversity. Low diversity arises from frequent disturbance and stressful conditions (i.e., high salinity and hypoxia), where vegetative reproduction and low competition result in mostly monotypic stands, with some differences in plant community influenced by flooding regime (
Authors
Scott T. Allen, Camille L. Stagg, Jorge Brenner, Kathleen L. Goodin, Don Faber-Langendoen, Christopher A. Gabler, Katherine Wirt Ames

Establishing a baseline: the amphibians of Lower Suwannee National Wildlife Refuge, Dixie and Levy counties, Florida

From 2002-2006, we used a variety of sampling techniques to survey the amphibians and water chemistry of Lower Suwannee National Wildlife Refuge in Florida’s Big Bend region. We recorded 23 amphibian species, 19 frogs and 4 salamanders. Species richness was lower than in other areas of the coastal Big Bend region to the north, perhaps due to a combination of proximity to the limits of species’ ran
Authors
C. Kenneth Dodd, William J. Barichivich, Steve A. Johnson, Margaret Gunzburger Aresco, Jennifer S. Staiger

Ecological resilience indicators for mangrove ecosystems

Mangrove ecosystems are coastal wetland ecosystems dominated by mangrove species that are typically found in the intertidal zone, characterized by frequently flooded saline soil conditions. The majority of the approximately 500,000 acres of mangrove ecosystem in the United States occurs in the NGoM, and almost all of that is in Florida, with over 90 percent in the four southern counties of Lee, Co
Authors
Richard H. Day, Scott T. Allen, Jorge Brenner, Kathleen Goodin, Don Faber-Langendoen, Katherine Wirt Ames

Lower lethal temperatures for nonnative freshwater fishes in Everglades National Park, Florida

Temperature is an important factor that shapes biogeography and species composition. In southern Florida, the tolerance of nonnative freshwater fishes to low temperatures is a critical factor in delineating their geographic spread. In this study, we provide empirical information on experimentally derived low-temperature tolerance limits of Banded Cichlid Heros severus and Spotfin Spiny Eel Macrogn
Authors
Pamela J. Schofield, Jeffrey L. Kline

Partial migration of the nurse shark, Ginglymostoma cirratum (Bonnaterre), from the Dry Tortugas Islands

Nurse sharks have not previously been known to migrate. Nurse sharks of the Dry Tortugas (DRTO) mating population have a highly predictable periodic residency cycle, returning to the Dry Tortugas Courtship and Mating Ground (DTCMG) annually (males) or bi- to triennially (females) during the June/July mating season. For 23 years we have followed the movements of 76 recaptured adults of a total of 1
Authors
Harold L. Pratt, Theo C. Pratt, Danielle Morley, Susan K. Lowerre-Barbieri, Angela Collins, Jeffrey C. Carrier, Kristen M. Hart, N.M. Whitney

How mangrove and salt marsh seedlings respond to CO2 and drought

Under our current changing climate, plants and animals must respond to rising sea levels, altered precipitation patterns, and increasing air and water temperatures and concentrations of greenhouse gases, including atmospheric carbon dioxide (CO2). While some species may adapt to changing conditions, these factors have the potential to drive latitudinal and elevational shifts in species distributio
Authors
Rebecca J. Howard

Spatial distribution and ecological risk assessment of heavy metals in coastal surface sediments in the Hebei Province offshore area, Bohai Sea, China

Seven hundred and nine surface sediment samples, along with deeper sediment samples, were collected from Hebei Province along the coastal section of the Bohai Sea, China, and analyzed for grain size, concentrations of organic carbon (Corg) and heavy metals (Cu, Pb, Zn, Cr, Cd, As, and Hg). Results indicated that the average concentrations in the sediments were 16.1 mg/kg (Cu), 19.4 mg/kg (Pb), 50
Authors
Xigui Ding, Siyuan Ye, Hongming Yuan, Ken W. Krauss

Succession in ecological education

As complex and dynamic systems, wetlands offer the opportunity to investigate and incorporate the ecological concept of succession in educational settings. For example, the well-known, classic hydrosere concept is illustrated in numerous ecology and life-science textbooks. In this chapter, the drawbacks of using the hydrosere successional concept are assessed, and two examples of using wetlands to
Authors
David J. Gibson, Beth A. Middleton

A parasitism-mutualism-predation model consisting of crows, cuckoos and cats with stage-structure and maturation delays on crows and cuckoos

In this paper, a parasitism-mutualism-predation model is proposed to investigate the dynamics of multi-interactions among cuckoos, crows and cats with stage-structure and maturation time delays on cuckoos and crows. The crows permit the cuckoos to parasitize their nestlings (eggs) on the crow chicks (eggs). In return, the cuckoo nestlings produce a malodorous cloacal secretion to protect the crow
Authors
Yantao Luo, Long Zhang, Zhidong Teng, Donald L. DeAngelis

Stream fish colonization but not persistence varies regionally across a large North American river basin

Many species have distributions that span distinctly different physiographic regions, and effective conservation of such taxa will require a full accounting of all factors that potentially influence populations. Ecologists recognize effects of physiographic differences in topography, geology and climate on local habitat configurations, and thus the relevance of landscape heterogeneity to species d
Authors
Kit Wheeler, Seth J. Wenger, Stephen J. Walsh, Zachary P. Martin, Howard L. Jelks, Mary Freeman