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Explore WARC's science publications.

Filter Total Items: 3350

Overview of prohibited and permitted plant regulatory listing systems

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
Authors
Randy G. Westbrooks, Alan V. Tasker

Early detection and rapid response

Prevention is the first line of defense against introduced invasive species - it is always preferable to prevent the introduction of new invaders into a region or country. However, it is not always possible to detect all alien hitchhikers imported in cargo, or to predict with any degree of certainty which introduced species will become invasive over time. Fortunately, the majority of introduced pl
Authors
Randy G. Westbrooks, Robert E. Eplee

Uni-directional consumer-resource theory characterizing transitions of interaction outcomes

A resource is considered here to be a biotic population that helps to maintain the population growth of its consumers, whereas a consumer utilizes a resource and in turn decreases its growth rate. Bi-directional consumer–resource (C–R) interactions have been the object of recent theory. In these interactions, each species acts, in some respects, as both a consumer and a resource of the other, whic
Authors
Y. Wang, D.L. DeAngelis, J.N. Holland

Geographic profiling to assess the risk of rare plant poaching in natural areas

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
Authors
J.A. Young, F.T. Van Manen, C.A. Thatcher

Search behavior of arboreal insectivorous migrants at gulf coast stopover sites in spring

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, frequency,
Authors
Chao-Chieh Chen, W.C. Barrow, K. Ouchley, R.B. Hamilton

Herpetofauna of the cedar glades and associated habitats of the Inner Central Basin of middle Tennessee

The cedar glades and barrens of the Inner Central Basin (ICB) of middle Tennessee support a unique and diverse flora and fauna and represent some of the state's most valued natural areas. We conducted herpetofaunal inventories of the cedar glades, associated barrens, cedar-hardwood forest, and adjacent aquatic habitats of the Stones River drainage of Middle Tennessee, focusing our sampling effort
Authors
M.L. Niemiller, Reynolds R. Graham, B.M. Glorioso, J. Spiess, B.T. Miller

Transfer and transformation of soil iron and implications for hydrogeomorpholocial changes in Naoli River catchment, sanjiang plain, Northeast China

Wetland soils are characterized by alternating redox process due to the fluctuation of waterlogged conditions. Iron is an important redox substance, and its transfer and transformation in the wetland ecosystem could be an effective indicator for the environment changes. In this paper, we selected the Naoli River catchment in the Sanjiang Plain, Northeast China as the study area to analyze the dyna
Authors
J. Ming, L. Xianguo, W. Hongqing, Z. Yuanchun, W. Haitao

A predator-prey model with a holling type I functional response including a predator mutual interference

The most widely used functional response in describing predator-prey relationships is the Holling type II functional response, where per capita predation is a smooth, increasing, and saturating function of prey density. Beddington and DeAngelis modified the Holling type II response to include interference of predators that increases with predator density. Here we introduce a predator-interference
Authors
G. Seo, D.L. DeAngelis

A field test of attractant traps for invasive Burmese pythons (Python molurus bivittatus) in southern Florida

Context. Invasive Burmese pythons (Python molurus bivittatus) are established over thousands of square kilometres of southern Florida, USA, and consume a wide range of native vertebrates. Few tools are available to control the python population, and none of the available tools have been validated in the field to assess capture success as a proportion of pythons available to be captured. Aims. Our
Authors
R.N. Reed, K.M. Hart, G.H. Rodda, F.J. Mazzotti, R.W. Snow, M. Cherkiss, R. Rozar, S. Goetz

Understanding interaction effects of climate change and fire management on bird distributions through combined process and habitat models

Avian conservation efforts must account for changes in vegetation composition and structure associated with climate change. We modeled vegetation change and the probability of occurrence of birds to project changes in winter bird distributions associated with climate change and fire management in the northern Chihuahuan Desert (southwestern U.S.A.). We simulated vegetation change in a process-base
Authors
Joseph D. White, Kevin J. Gutzwiller, Wylie C. Barrow, Lori Johnson-Randall, Lisa Zygo, Pamela Swint