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Publications

Browse publications authored by our scientists.  Publications available are: USGS-authored journal articles, series reports, book chapters, other government publications, and more. **Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

Filter Total Items: 3984

Cambarus loughmani, a new species of crayfish (Decapoda: Cambaridae) endemic to the pre-glacial Teays River Valley in West Virginia, USA

A new species of crayfish, Cambarus loughmani sp. nov., is described from the preglacial Teays River Valley of Cabell, Kanawha, Lincoln, Mason, and Putnam counties, West Virginia. The species was previously considered to be part of the Cambarus dubius complex. Loughman et al. restricted C. dubius to an orange colour morph found in central and northern portions of the Allegheny Mountains and Appala
Authors
David A. Foltz, Nichole Sadecky, Greg Myers, Jr. Fetzner, Stuart A. Welsh, Whitney Stockner, Mael Glon, Roger F. Thoma

Demographic rates of two southeastern populations of Painted Bunting, 2007–2015

Painted Buntings (Passerina ciris) have been declining in the southeastern United States since the 1970s. A recent demographic assessment highlighted the importance of estimating demographic parameters, which have received little attention to date. The dearth of information is troublesome because attempts to reverse declining trends require a better understanding of the relationship between habita
Authors
Liani M. Yirka, Jaime A. Collazo, Brian J. O'Shea, J.A. Gerwin, James A. Rotenberg, David T. Cobb

Process convolution approaches for modeling interacting trajectories

Gaussian processes are a fundamental statistical tool used in a wide range of applications. In the spatiotemporal setting, several families of covariance functions exist to accommodate a wide variety of dependence structures arising in different applications. These parametric families can be restrictive and are insufficient in some situations. In contrast, process convolutions represent a flexible
Authors
Henry R. Scharf, Mevin Hooten, Devin S. Johnson, John W. Durban

On the relationship between conditional (CAR) and simultaneous (SAR) autoregressive models

We clarify relationships between conditional (CAR) and simultaneous (SAR) autoregressive models. We review the literature on this topic and find that it is mostly incomplete. Our main result is that a SAR model can be written as a unique CAR model, and while a CAR model can be written as a SAR model, it is not unique. In fact, we show how any multivariate Gaussian distribution on a finite set of p
Authors
Jay M. Ver Hoef, Ephraim M. Hanksb, Mevin Hooten

Effects of water-level management and hatchery supplementation on kokanee recruitment in Lake Pend Oreille, Idaho

Resource managers have been attempting to recover the kokanee (Oncorhynchus nerka) population in Lake Pend Oreille, Idaho for more than three decades using an annual stocking program and an experimental water-level management strategy. This study evaluated the effect of both management actions on kokanee recruitment. A bootstrap-based generalized Ricker model was used to test if wild kokanee recru
Authors
Steven L. Whitlock, Michael Quist, Andrew M. Dux

Density of American black bears in New Mexico

Considering advances in noninvasive genetic sampling and spatially explicit capture–recapture (SECR) models, the New Mexico Department of Game and Fish sought to update their density estimates for American black bear (Ursus americanus) populations in New Mexico, USA, to aide in setting sustainable harvest limits. We estimated black bear density in the Sangre de Cristo, Sandia, and Sacramento Mount
Authors
Matthew J. Gould, James W. Cain, Gary W. Roemer, William R. Gould, Stewart Liley

Fitting N-mixture models to count data with unmodeled heterogeneity: Bias, diagnostics, and alternative approaches

Monitoring animal populations is central to wildlife and fisheries management, and the use of N-mixture models toward these efforts has markedly increased in recent years. Nevertheless, relatively little work has evaluated estimator performance when basic assumptions are violated. Moreover, diagnostics to identify when bias in parameter estimates from N-mixture models is likely is largely unexplor
Authors
Adam Duarte, M. J. Adams, James Peterson

Seasonal food habits of introduced blue catfish in Lake Oconee, Georgia

Blue catfish (Ictalurus furcatus) are native to the Coosa River drainage in northwest Georgia but have been widely introduced outside of this range including Lake Oconee, a 7677-ha impoundment on the Oconee River in central Georgia. Blue catfish abundance and growth rates have increased dramatically since their introduction in Lake Oconee, but their food habits are unknown. Therefore, food habits
Authors
Cecil A. Jennings, Geoffrey E. Mitchell, Chris Nelson

Enhancing quantitative approaches for assessing community resilience

Scholars from many different intellectual disciplines have attempted to measure, estimate, or quantify resilience. However, there is growing concern that lack of clarity on the operationalization of the concept will limit its application. In this paper, we discuss the theory, research development and quantitative approaches in ecological and community resilience. Upon noting the lack of methods th
Authors
W. C. Chuang, A.S. Garmestani, T. N. Eason, T. L. Spanbauer, H. B. Fried-Peterson, C. P. Roberts, Shana M. Sundstrom, J.L. Burnett, David G. Angeler, Brian C. Chaffin, L. Gunderson, Dirac Twidwell, Craig R. Allen

Wildlife habitat management on college and university campuses

With the increasing involvement of higher education institutions in sustainability movements, it remains unclear to what extent college and university campuses address wildlife habitat. Many campuses encompass significant areas of green space with potential to support diverse wildlife taxa. However, sustainability rating systems generally emphasize efforts like recycling and energy conservation ov
Authors
Tierney Bosci, Paige S. Warren, Rick W. Harper, Stephen DeStefano

Fight and air exposure times of caught and released salmonids from the South Fork Snake River

Catch-and-release regulations are among the most common types of fishing regulations. In recent years, concerns have arisen regarding the exposure of fish to air during catch-and-release angling. The purpose of our study was to quantify the length of time angled fish were exposed to air by anglers in a typical catch-and-release fishery and relate it to the lengths of time reported to produce negat
Authors
Curtis J. Roth, Daniel J. Schill, Michael C. Quist

The non-linear, interactive effects of population density and climate drive the geographical patterns of waterfowl survival

On-going climate change has major impacts on ecological processes and patterns. Understanding the impacts of climate on the geographical patterns of survival can provide insights to how population dynamics respond to climate change and provide important information for the development of appropriate conservation strategies at regional scales. It is challenging to understand the impacts of climate
Authors
Qing Zhao, G. Scott Boomer, William L. Kendall