Publications

Silver carp Hypophthalmichthys molitrix (Cyprinidae) is native to China and has been introduced to over 80 countries. The extent of genetic diversity in introduced silver carp and the genetic divergence between introduced and native populations remain largely unknown. In this study, 241 silver carp sampled from three major native rivers and two non-native rivers (Mississippi River and...

Search behavior of arboreal insectivorous migrants was studied at three stopover sites along the northern coast of the Gulf of Mexico during spring migrations, 1993–1995. We examined if search behavior was affected by phylogeny, or by environmental factors. A sequence of search movements (hop, flutter, or flight) in a foraging bout was recorded for each migrant encountered. Search rate...

An interlaboratory comparison of acid-volatile sulfide (AVS) and simultaneously extracted nickel (SEM_Ni) measurements of sediments was conducted among five independent laboratories. Relative standard deviations for the seven test samples ranged from 5.6 to 71% (mean = 25%) for AVS and from 5.5 to 15% (mean = 10%) for SEM_Ni. These results are in stark contrast to a recently published...

Premise of the Study: Climate warming is predicted to have far‐reaching effects on the distribution of species, but those effects may depend on the flexibility of regenerating species in responding to climate gradients. We conducted a study to determine whether the variation in the response of seed banks to temperature varied across the latitudinal range of Taxodium distichum swamps in...

Winter diet of the Short-eared Owl (Asio flammeus) in Texas is little known. We investigated the diet of Short-eared Owls wintering in McMullen County, in subtropical Texas, by analyzing the contents of 129 pellets collected over two winters (28 November 2007 to 22 February 2008 and 11 December 2008 to 11 February 2009) and conducted a latitudinal-based comparison of published diet...

From September to November 2000, United States Fish and Wildlife Service biologists investigated incidents involving 221 bird deaths at 3 mine sites located in New Mexico and Arizona. These bird deaths primarily involved passerine and waterfowl species and were assumed to be linked to consumption of acid metalliferous water (AMW). Because all of the carcasses were found in or near...

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...

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...

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...

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...

A draft update of the U.S. Environmental Protection Agency ambient water quality criteria (AWQC) for ammonia substantially lowers the ammonia AWQC, primarily due to the inclusion of toxicity data for freshwater mussels. However, most of the mussel data used in the updated AWQC were generated from water-only exposures and limited information is available on the potential influence of the...