Publications

A uni-directional consumer–resource system of two species is analyzed. Our aim is to understand the mechanisms that determine how the interaction outcomes depend on the context of the interaction; that is, on the model parameters. The dynamic behavior of the model is described and, in particular, it is demonstrated that no periodic orbits exist. Then the parameter (factor) space is shown to be div

Context: Hunting-related (hereafter harvest) mortality is assumed to be compensatory in many exploited species. However, when harvest mortality is additive, hunting can lead to population declines, especially on public land where hunting pressure can be intense. Recent studies indicate that excessive hunting may have contributed to the decline of a northern bobwhite (Colinus virginianus) populatio

Nightlight surveys are commonly used to evaluate status and trends of crocodilian populations, but imperfect detection caused by survey- and location-specific factors makes it difficult to draw population inferences accurately from uncorrected data. We used a two-stage hierarchical model comprising population abundance and detection probability to examine recent abundance trends of American alliga

We demonstrate the use of an expert-assisted spatial model to examine geographic factors influencing the poaching risk of a rare plant (American ginseng, Panax quinquefolius L.) in Shenandoah National Park, Virginia, USA. Following principles of the analytic hierarchy process (AHP), we identified a hierarchy of 11 geographic factors deemed important to poaching risk and requested law enforcement p

The lower part of the Wilcox Group of northwest Louisiana contains shallow (less than 500 ft) coal deposits that are mined for use in mine-mouth electric power-generating plants. The coal deposits, which are lignite A in apparent rank (Pierce et al., 2011), occur on the eastern part of the Sabine uplift (Figure 1). The coal zones and associated strata in the assessment area generally dip away from

No abstract available.

No abstract available.

Beach vitex (Vitex rotundifolia L. f.), a woody vine from Korea, was introduced into the United States as a dune stabilization plant in the mid-1980s. By the mid- to late-1990s, Beach vitex was observed spreading from landscape plantings along the South Carolina coast, crowding out native dune species. In 2003, in response to concerns about possible impacts of the plant on native dune species, as

Witchweed [(Striga asiatica (L.) O. Kuntze)] is a parasitic weed from Asia and Africa that attaches to the roots of grasses and grass crops such as corn and sorghum. Witchweed was first detected in the western hemisphere in a corn field in Columbus County, North Carolina, in July, 1956. Since that time, a federal/state cooperative program has eliminated over 99% of the 432,000+ acres that have bee

Pest risk analysis is a process that evaluates the risks involved with a proposed species to help determine whether it should be permitted or denied entry into a country, and how the risks could be managed if it is imported. The prohibited listing approach was developed in the late 1800s and early 1900s in response to outbreaks of plant and animals pests such as foot and mouth disease of livestock

No abstract available.

Compensatory changes in juvenile survival allow fish stocks to maintain relatively constant recruitment across a wide range of stock sizes (and levels of fishing), but few studies have experimentally explored recruitment compensation in fish populations. We evaluated the potential for recruitment compensation in largemouth bass Micropterus salmoides by stocking six 0.4-ha hatchery ponds with adult