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Inference for occupancy and occupancy dynamics

This chapter deals with the estimation of occupancy as a state variable to assess the status of, and track changes in, species distributions when sampling with camera traps. Much of the recent interest in occupancy estimation and modeling originated from the models developed by MacKenzie et al. (2002, 2003), although similar methods were developed independently (Azuma et al. 1990; Bayley and Peter
Authors
Allan F. O'Connell, Larissa L. Bailey

Estimation of demographic parameters in a tiger population from long-term camera trap data

Chapter 7 (Karanth et al.) illustrated the use of camera trapping in combination with closed population capture–recapture (CR) models to estimate densities of tigers Panthera tigris. Such estimates can be very useful for investigating variation across space for a particular species (e.g., Karanth et al. 2004) or variation among species at a specific location. In addition, estimates of density cont
Authors
K. Ullas Karanth, James D. Nichols

Science, conservation, and camera traps

Biologists commonly perceive camera traps as a new tool that enables them to enter the hitherto secret world of wild animals. Camera traps are being used in a wide range of studies dealing with animal ecology, behavior, and conservation. Our intention in this volume is not to simply present the various uses of camera traps, but to focus on their use in the conduct of science and conservation. In t
Authors
James D. Nichols, K. Ullas Karanth, Allan F. O'Connel

Estimating tiger abundance from camera trap data: Field surveys and analytical issues

Automated photography of tigers Panthera tigris for purely illustrative purposes was pioneered by British forester Fred Champion (1927, 1933) in India in the early part of the Twentieth Century. However, it was McDougal (1977) in Nepal who first used camera traps, equipped with single-lens reflex cameras activated by pressure pads, to identify individual tigers and study their social and predatory
Authors
K. Ullas Karanth, James D. Nichols

A decision-analytic approach to the optimal allocation of resources for endangered species consultation

The resources available to support conservation work, whether time or money, are limited. Decision makers need methods to help them identify the optimal allocation of limited resources to meet conservation goals, and decision analysis is uniquely suited to assist with the development of such methods. In recent years, a number of case studies have been described that examine optimal conservation de
Authors
Sarah J. Converse, Kevin J. Shelley, Steve Morey, Jeffrey Chan, Andrea LaTier, Carolyn Scafidi, Deborah T. Crouse, Michael C. Runge

A conduit dilation model of methane venting from lake sediments

Methane is a potent greenhouse gas, but its effects on Earth's climate remain poorly constrained, in part due to uncertainties in global methane fluxes to the atmosphere. An important source of atmospheric methane is the methane generated in organic-rich sediments underlying surface water bodies, including lakes, wetlands, and the ocean. The fraction of the methane that reaches the atmosphere depe
Authors
B.P. Scandella, C. Varadharajan, Harold F. Hemond, C. Ruppel, R. Juanes

2011 statistical abstract of the United States

<p>The <i>Statistical Abstract of the United States</i>, published since 1878, is the authoritative and comprehensive summary of statistics on the social, political, and economic organization of the United States.</p> <br/> <p>Use the Abstract as a convenient volume for statistical reference, and as a guide to sources of more information both in print and on the Web.</p> <br/> <p>Sources of data i
Authors
Joseph M. Krisanda

Inside the crater, outside the crater: Stratigraphic details of the margin of the Chesapeake Bay impact structure, Virginia, USA

Two cores at the outer margin of the Chesapeake Bay impact structure show significant structural and depositional variations that illuminate its history. Detailed stratigraphy of the Watkins School core reveals that this site is outside the disruption boundary of the crater with respect to its lower part (nonmarine Cretaceous Potomac Formation), but just inside the boundary with respect to its upp
Authors
Lucy E. Edwards, David S. Powars, J. Wright Horton,, Gregory Gohn, Jean Self-Trail, R. J. Litwin

USGS-NPS Servicewide Benthic Mapping Program (SBMP) workshop report

Executive SummaryThe National Park Service (NPS) Inventory and Monitoring (I&M) Program recently allocated funds to initiate a benthic mapping program in ocean and Great Lakes parks in alignment with the NPS Ocean Park Stewardship 2007-2008 Action Plan. Seventy-four (ocean and Great Lakes) parks, spanning more than 5,000 miles of coastline, many affected by increasing coastal storms and other natu
Authors
Christopher S. Moses, Amar Nayagandhi, John Brock, Rebecca Beavers

Delaware Water Gap; a geology classroom

No abstract available.
Authors
Jack B. Epstein