Skip to main content
U.S. flag

An official website of the United States government

Publications

Explore WARC's science publications.

Filter Total Items: 3374

Dry years decrease abundance of American alligators in the Florida Everglades

The Everglades has been greatly reduced and is threatened by land use change and altered hydrology. The Comprehensive Everglades Restoration Plan calls for monitoring and assessment of key ecosystem attributes, one of which is abundance of American alligators. We examined 10 years of alligator night spotlight counts from Arthur R. Marshall Loxahatchee National Wildlife Refuge along two canals and
Authors
J. Hardin Waddle, Laura A. Brandt, Brian M. Jeffery, Frank J. Mazzotti

Forested wetland habitat

A forested wetland (swamp) is a forest where soils are saturated or flooded for at least a portion of the growing season, and vegetation, dominated by trees, is adapted to tolerate flooded conditions. A tidal freshwater forested wetland is a forested wetland that experiences frequent but short-term surface flooding via tidal action, with average salinity of soil porewater less than 0.5 g/l. It is
Authors
Jamie A. Duberstein, Ken W. Krauss

Mangrove sedimentation and response to relative sea-level rise

Mangroves occur on upper intertidal shorelines in the tropics and subtropics. Complex hydrodynamic and salinity conditions influence mangrove distributions, primarily related to elevation and hydroperiod; this review considers how these adjust through time. Accumulation rates of allochthonous and autochthonous sediment, both inorganic and organic, vary between and within different settings. Abunda
Authors
CD Woodroffe, K. Rogers, Karen L. McKee, CE Lovelock, IA Mendelssohn, N. Saintilan

Compact development and VMT: environmental determinism, self-selection, or some of both?

There is a long-running debate in the planning literature about the effects of the built environment on travel behavior and the degree to which apparent effects are due to the tendency of households to self-select into neighborhoods that reinforce their travel preferences. Those who want to walk will choose walkable neighborhoods, and those who want to use transit will choose transit-served neighb
Authors
Reid Ewing, Shima Hamidi, James B. Grace

Factors affecting individual foraging specialization and temporal diet stability across the range of a large “generalist” apex predator

Individual niche specialization (INS) is increasingly recognized as an important component of ecological and evolutionary dynamics. However, most studies that have investigated INS have focused on the effects of niche width and inter- and intraspecific competition on INS in small-bodied species for short time periods, with less attention paid to INS in large-bodied reptilian predators and the effe
Authors
Adam E. Rosenblatt, James C. Nifong, Michael R. Heithaus, Frank J. Mazzotti, Michael S. Cherkiss, Brian M. Jeffery, Ruth M. Elsey, Rachel A. Decker, Brian R. Silliman, Louis J. Guillette, Russell H. Lowers, Justin C. Larson

Annual growth patterns of baldcypress (Taxodium distichum) along salinity gradients

The effects of salinity on Taxodium distichum seedlings have been well documented, but few studies have examined mature trees in situ. We investigated the environmental drivers of T. distichum growth along a salinity gradient on the Waccamaw (South Carolina) and Savannah (Georgia) Rivers. On each river, T. distichum increment cores were collected from a healthy upstream site (Upper), a moderately
Authors
Brenda L. Thomas, Thomas W. Doyle, Ken W. Krauss

Evaluation of habitat suitability index models by global sensitivity and uncertainty analyses: a case study for submerged aquatic vegetation

Habitat suitability index (HSI) models are commonly used to predict habitat quality and species distributions and are used to develop biological surveys, assess reserve and management priorities, and anticipate possible change under different management or climate change scenarios. Important management decisions may be based on model results, often without a clear understanding of the level of unc
Authors
Zuzanna Zajac, Bradley Stith, Andrea C. Bowling, Catherine A. Langtimm, Eric D. Swain

Responses to water depth and clipping of twenty−three plant species in an Indian monsoonal wetland

Responses of species to disturbances give insights into how species might respond to future wetland changes. In this study, species of monsoonal wetlands belonging to various functional types (graminoid and non−graminoid emergents, submersed aquatic, floating−leaved aquatic) varied in their growth responses to water depth and harvesting. We tested the effects of water depth (moist soil, flooded) a
Authors
Beth A. Middleton, Arnold van der Valk, Craig B. Davis

Adaptive harvest management: Adjustments for SEIS 2013

This report provides a summary of revised methods and assessment results based on updated adaptive harvest management (AHM) protocols developed in response to the preferred alternative specified in the Final Supplemental Environmental Impact Statement on the Issuance of Annual Regulations Permitting the Hunting of Migratory Birds (SEIS; U.S. Department of the Interior 2013). We describe necessary
Authors
Scott Boomer, Fred A. Johnson, Guthrie S. Zimmerman

Etheostoma brevirostrum (Holiday Darter)

The life history of the Holiday Darter is incompletely known. Only reproductive behavior (Johnston and Shute 1997; Anderson 2009), habitat use, and spawning seasons (Anderson 2009) have been studied. However, based on similarity of life history attributes among snubnose darters (Carney and Burr 1989; Johnston and Haag 1996; Khudamrongsawat et al. 2005), the Holiday darter probably lives 3+ years a
Authors
Noel M. Burkhead

Novel associations between contaminant body burdens and biomarkers of reproductive condition in male Common Carp along multiple gradients of contaminant exposure in Lake Mead National Recreation Area, USA

Adult male Common Carp were sampled in 2007/08 over a full reproductive cycle at Lake Mead National Recreation Area. Sites sampled included a stream dominated by treated wastewater effluent, a lake basin receiving the streamflow, an upstream lake basin (reference), and a site below Hoover Dam. Individual body burdens for 252 contaminants were measured, and biological variables assessed included ph
Authors
Reynaldo Patiño, Matthew M. VanLandeghem, Steven L. Goodbred, Erik Orsak, Jill A. Jenkins, Kathy R. Echols, Michael R. Rosen, Leticia Torres