A5043600598- Wildlife Ecology and Conservation
- Fish Ecology and Management Studies
- Census and Population Estimation
- Avian ecology and behavior
- Marine and fisheries research
- Survey Sampling and Estimation Techniques
- Species Distribution and Climate Change
- Animal Ecology and Behavior Studies
- Marine animal studies overview
- Rangeland and Wildlife Management
- Bayesian Methods and Mixture Models
- Genetic and phenotypic traits in livestock
- Fire effects on ecosystems
- Biomedical and Chemical Research
- Statistical Methods and Bayesian Inference
- Data-Driven Disease Surveillance
- Water Quality and Resources Studies
- Ecology and Vegetation Dynamics Studies
- Advanced Statistical Methods and Models
- Data Analysis with R
- Insect Utilization and Effects
- Survey Methodology and Nonresponse
- Statistics Education and Methodologies
- Aquatic Invertebrate Ecology and Behavior
- Agriculture and Biological Studies
Simon Fraser University
2013-2025
University of Vienna
1907-2024
University of Illinois Urbana-Champaign
2024
Frankfurt Institute for Advanced Studies
2017
Goethe University Frankfurt
2017
University of British Columbia
2009-2014
University of Victoria
2009
Fisheries and Oceans Canada
2009
University of Auckland
1999
University of Manitoba
1988-1995
We trace the development of a likelihood function representation for open-population capture-recapture (Jolly-Seber) experiment. find that modelling birth process in general model is not consistent with reduced death-only and all formulations to date lead difficulties imposing constraints upon parameters process. propose generalisation usual Jolly-Seber models births using multinomial distribution from super-population. show how this leads simplifications numerical optimization can now be...
The literature describing methods for estimating animal abundance and related parameters continues to grow. This paper reviews recent developments in the subject over past seven years updates two previous reviews.
Tag-recovery data are used to estimate migration rates among a set of strata. The model formulation is simple matrix extension the tag-recovery experiment discussed by Brownie et al. (1985, Statistical Inference from Band-Recovery Data-A Handbook, 2nd edition, Washington, D.C.: U.S. Department Interior). Estimation more difficult because convolution parameters between release and recovery this may cause estimates survival/ have low precision. Derived emigration, immigration, harvest...
Abstract Estimates of species' vital rates and an understanding the factors affecting those parameters over time space can provide crucial information for management conservation. We used mark–recapture, reproductive output, territory occupancy data collected during 1985–2013 to evaluate population processes Northern Spotted Owls (Strix occidentalis caurina) in 11 study areas Washington, Oregon, northern California, USA. estimated apparent survival, fecundity, recruitment, rate change, local...
Species sensitivity distributions (SSDs) are cumulative probability that used to estimate the percent of species affected by a given concentration chemical.The affects 5% is referred as Hazard Concentration (HC).Hazard concentrations for derivation environmental quality criteria and ecological risk assessment contaminated ecosystems (Posthuma, Suter II, & Traas, 2001).
ABSTRACT We analyzed demographic data from northern spotted owls (Strix occidentalis caurina) 14 study areas in Washington, Oregon, and California for 1985–2003. The purpose of our analyses was to provide an assessment the status trends owl populations throughout most their geographic range. made up approximately 12% range subspecies included federal, tribal, private, mixed federal private lands. also all major forest types that inhabits. followed rigorous protocols were developed a priori...
One of the basic assumptions central to analysis capture-recapture experiments is that all marked animals remain in population under study for duration sampling, or if they migrate out do so permanently. Burnham (1993, Marked Individuals Study Bird Populations,199-213), Kendall and Nichols (1995, Applied Statistics 22, 751-762), Kendall, Nichols, Hines (in press) showed completely random temporary emigration influences only estimates probability capture, these now estimating product rate...
Conservation of grizzly bears (Ursus arctos) is often controversial and the disagreement focused on estimates density used to calculate allowable kill. Many recent bear are now available but field-based will never be for more than a small portion hunted populations. Current methods predicting in areas management interest subjective untested. Objective have been proposed, these statistical models so dependent results from individual study that do not generalize well. We built regression...
ABSTRACT Federally listed as threatened in 1990 primarily because of habitat loss, the northern spotted owl ( Strix occidentalis caurina ) has continued to decline despite conservation efforts resulting forested being reserved throughout its range. Recently, there is growing evidence congeneric invasive barred varia may be responsible for by excluding owls from their preferred habitat. We used a long‐term demographic study coastal California basis pilot removal experiment. Our demography...
The nutritional status of Atlantic salmon Salmo salar parr was assessed by examining how proximate body composition and energy content (kJ g −1 ) were associated with the habitat rearing origin utilizing fluvial or lacustrine areas. Comparisons made among sampling sites within two habitats, as well between major types applying both fixed effect random models. Mean protein concentration varied from 13·87 to 15·67% sites, 14·96 16·38% locations. fat ranged 1·71 3·32% 2·22 4·29% locations,...
The northern spotted owl (Strix occidentalis caurina) inhabits older coniferous forests in the Pacific Northwest and has been at center of forest management issues this region. immediate threats to federally listed species include habitat loss competition with barred owls varia), which invaded from eastern North America. We conducted a prospective meta-analysis assess population trends factors affecting those using 26 years survey capture-recapture data 11 study areas across owls' geographic...
Ivory poaching continues to threaten African elephants. We (1) used criminology theory and literature evidence generate hypotheses about factors that may drive, facilitate or motivate poaching, (2) identified datasets representing these factors, (3) tested those with strong sufficient data quality for empirical associations poaching. advance on previous analyses of correlates elephant by using additional leveraging new previously untested explanatory variables. Using 10 286 illegally killed...
We describe some recent developments in the POPAN system for analysis of mark-recapture data from Jolly-Seber (IS) type experiments and how this applies to banding data. discuss extra requirements JS studies, which provide estimates abundance entry/birth rates, over survival (CJS) studies. implements a unified likelihood approach using constrained maximization show differs design-matrix used CJS software. illustrate application constraints covariate models across groups with examples drawn...
Summary Recent developments in the Cormack–Jolly–Seber (CJS) model for analyzing capture–recapture data have focused on allowing capture and survival rates to vary between individuals. Several methods been developed which are functions of auxiliary variables that may be discrete, constant over time, or apply population as a whole, but problem has not solved continuous covariates with both time individual. This article proposes new method handle such by modeling changes via diffusion process...
We describe a method of estimating the spawning escapement coho salmon (Oncorhynchus kisutch) from capture–recapture data. Traditional analyses do not directly provide estimates escapements; however, we show how simple modifications to Jolly–Seber can estimate total number fish returning river including those that enter and die between sampling occasions. Spawning runs Pacific were simulated their escapements estimated using capture–recapture. The performance maximum likelihood estimators...
We describe a new estimator of population size that can be formed when independent sightings are made marked and unmarked animals in closed where subset the is individually marked. Each animal must bear unique mark but number alive unknown. The estimate used no recaptures or removals possible during experiment. An example estimating immature bald eagles (Haliaeetus leucocephalus) on lake some years after banding nestlings. derive maximum likelihood estimates for marks, we show how to develop...