Publications

Drought frequency and intensity are projected to increase throughout the southeastern USA, the natural range of loblolly pine (Pinus taeda L.), and are expected to have major ecological and economic implications. We analyzed the carbon and oxygen isotopic compositions in tree ring cellulose of loblolly pine in a factorial drought (~30% throughfall reduction) and fertilization experiment

Development of integrated population models (IPMs) assume the absence of systematic bias in monitoring programs, yet many potential sources of systematic bias in monitoring data exist (e.g., under-counts of abundance). By integrating multiple sources of data, we can assess whether various sources of monitoring data provide consistent inferences about changes in population size and, thus...

Wetlands provide numerous ecosystem functions such as water purification, nutrient cycling, and wildlife habitat. Avian populations are indicators of wetland health, and understanding their responses to extreme events can aid in targeting restoration efforts following disturbance. Here, we assessed the habitat selection of six coastal wetland bird species (American Bittern, Black-crowned...

Streams are influenced by watershed-scale factors, such as climate, geology, topography, hydrology, and soils, which mostly vary naturally among sites, as well as human factors, agriculture and urban development. Thus, natural factors could complicate assessment of human disturbance. In the present study, we use structural equation modeling and data from the 2008-2009 United States...

Sesarmid crabs play an important role in organic matter and carbon cycling of mangrove forests. Visual observations and gut content studies have verified that sesarmid crabs are feeding on mangrove leaves, yet stable isotopes of carbon and nitrogen (13C and 15N) have indicated that leaf litter is not assimilated as a food source. Sesarmid crabs tend to be much more enriched in 13C than...

The Deepwater Horizon (DWH) oil spill from April to July of 2010 contaminated Gulf of Mexico waters through release of an estimated 4.1 × 106 barrels of oil. Beginning in June of 2010, semipermeable membrane devices (SPMDs) were deployed near areas with sensitive marine habitats (Alabama Alps and Western Shelf) potentially exposed to that oil. Elevated TPAH50 concentrations, flux rates...

Serum iron concentration is usually decreased in true iron deficiency and with inflammatory disease in man and domestic animals. Serum total iron binding capacity (TIBC) may be increased in true iron deficiency and decreased with inflammatory disease. This prospective study was designed to measure serum iron analytes in healthy free-ranging and housed Florida manatees (Trichechus manatus

The purpose of this study was to determine the elevation dynamics of a created tidal marsh on the North Carolina coast. Deep rod surface elevation tables (RSET) and feldspar marker horizons (MH) were installed in plots to measure net surface elevation changes and to quantify contributing processes. Twelve total plots were placed on four elevation gradient transects (three transects...

The African Jewelfish, Hemichromis letourneuxi, is an invasive, predatory cichlid fish introduced at least once to Florida. Its native range is in northern Africa. First encountered in Miami in the 1960s, it has since been found west and north within the State of Florida. It thrives in a wide range of aquatic habitats, including shallow, vegetated or rocky areas of canals, tidal creeks...

This paper considers a two-patch system with asymmetric diffusion rates, in which exploitable resources are included. By using dynamical system theory, we exclude periodic solution in the one-patch subsystem and demonstrate its global dynamics. Then we exhibit uniform persistence of the two-patch system and demonstrate uniqueness of the positive equilibrium, which is shown to be...

Seeing an animal hanging lifelessly from a snare is a heart-wrenching experience. Knowing that most animals caught in snares are left to rot without being used for meat or any other purpose might be worse. Over an eight-year period, 2001–2009, we recorded 10,231 incidents of illegal hunting in a wildlife conservation area in southeastern Zimbabwe, the Savé Valley Conservancy (SVC). Sixty...

Foundation plant species play a critical role in coastal wetlands, often modifying abiotic conditions that are too stressful for most organisms and providing the primary habitat features that support entire ecological communities. Here, we consider the influence of climatic drivers on the distribution of foundation plant species within coastal wetlands of the conterminous USA. Using...