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Publications

These publications showcase the significant science conducted in our Science Centers.

Filter Total Items: 16786

The importance of environmental variability and management control error to optimal harvest policies

State-dependent strategies (SDSs) are the most general form of harvest policy because they allow the harvest rate to depend, without constraint, on the state of the system. State-dependent strategies that provide an optimal harvest rate for any system state can be calculated, and stochasticity can be appropriately accommodated in this optimization. Stochasticity poses 2 challenges to harvest polic
Authors
C.M. Hunter, M.C. Runge

Capture-recapture analysis for estimating manatee reproductive rates

Modeling the life history of the endangered Florida manatee (Trichechus manatus latirostris) is an important step toward understanding its population dynamics and predicting its response to management actions. We developed a multi-state mark-resighting model for data collected under Pollock's robust design. This model estimates breeding probability conditional on a female's breeding state in the p
Authors
W. L. Kendall, C.A. Langtimm, C.A. Beck, M.C. Runge

Contribution of natural history collection data to biodiversity assessment in national parks

There has been mounting interest in the use of museum and herbaria collections to assess biodiversity; information is often difficult to locate and access, however, and few recommendations are available for effectively using natural history collections. As part of an effort to inventory vertebrates and vascular plants in U.S. national parks, we searched manually and by computer for specimens origi
Authors
A.F. O'Connell, A.T. Gilbert, J. S. Hatfield

A specimen of the Varied Thrush from Florida

No abstract available.
Authors
G.E. Woolfenden, R.C. Banks

A stage-based model of manatee population dynamics

A stage-structured population model for the Florida manatee (Trichechus manatus latirostris) was developed that explicitly incorporates uncertainty in parameter estimates. The growth rates calculated with this model reflect the status of the regional populations over the most recent 10-yr period. The Northwest and Upper St. Johns River regions have growth rates (8) of 1.037 (95% interval, 1.016?1.
Authors
M.C. Runge, C.A. Langtimm, W. L. Kendall

Forty-fifth supplement to the American Ornithologists' Union Check-list of North American Birds

This is the fourth Supplement since publication of the 7th edition of the Check-list of North American Birds (American Ornithologists' Union [AOU] 1998). It summarizes decisions made by the AOU's Committee on Classification and Nomenclature between 1 January 2003 and 31 December 2003.
Authors
R.C. Banks, C. Cicero, J.L. Dunn, A.W. Kratter, P.C. Rasmussen, J.V. Remsen, J.D. Rising, D.F. Stotz

Estimation of tiger densities in the tropical dry forests of Panna, Central India, using photographic capture-recapture sampling

Tropical dry-deciduous forests comprise more than 45% of the tiger (Panthera tigris) habitat in India. However, in the absence of rigorously derived estimates of ecological densities of tigers in dry forests, critical baseline data for managing tiger populations are lacking. In this study tiger densities were estimated using photographic capture–recapture sampling in the dry forests of Panna Tiger
Authors
K.Ullas Karanth, Raghunandan S. Chundawat, James D. Nichols, N. Samba Kumar

Effects of lead-contaminated sediment and nutrition on mallard duckling brain growth and biochemistry

Day-old mallard (Anas platyryhnchos) ducklings received either a clean sediment (24%) supplemented control diet, Coeur d'Alene River Basin, Idaho (CDARB) sediment (3449 ug/g lead) supplemented diets at 12% or 24%, or a positive control diet (24% clean sediment with equivalent lead acetate to the 24% CDARB diet) for 6 weeks. The 12% CDARB diet resulted in a geometric mean concentration of 396 ppb (
Authors
E. Douglas-Stroebel, D. J. Hoffman, G. L. Brewer, L. Sileo

Sex ratio estimation and survival analysis for Orthetrum coerulescens (Odonata, Libellulidae)

There is controversy over whether uneven sex ratios observed in mature dragonfly populations are a mere artifact resulting from the higher observability of males. Previous studies have at best made indirect inference about sex ratios by analysis of survival or recapture rates. Here, we obtain direct estimates of sex ratio from capture-recapture data based on the Cormack-Jolly-Seber model. We studi
Authors
M. Kery, L. Juillerat

Detecting warning signs of trouble within population fluctuations: using capture-recapture modeling to uncover changes in population dynamics leading to declines

An intensive mark-recapture/resighting program has been carried out on the Roseate Terns nesting at Falkner Island, Connecticut, since the late 1980s as part of a regional study of the metapopulation dynamics and ecology of the endangered Northwest Atlantic breeding population of this species. Substantial losses of tern eggs and chicks to predation at this colony site began in 1996 when at least
Authors
J. A. Spendelow, J. D. Nichols, W. L. Kendall, J. E. Hines, J. S. Hatfield, I.C.T. Nisbet

Tumor prevalence and biomarkers of exposure in brown bullhead (Ameiurus nebulosus) from Back River, Furnace Creek, and Tuckahoe River, Maryland

Brown bullheads (Ameiurus nebulosus) were collected from 2 locations near Baltimore, Maryland, Back River and Furnace Creek, and 1 (reference) location, Tuckahoe River, to compare the prevalence of tumors (liver and skin) and visible skin lesions (fin erosion and abnormal barbels). Cytochrome P450 activity measured as ethoxyresorufin-O-deethylase, biliary PAH-like fluorescent metabolites, and fill
Authors
A.E. Pinkney, J.C. Harshbarger, E.B. May, M. J. Melancon