Results 11 to 20 of about 83,949 (294)
Methods in Ecology and Evolution, 2021 Line‐transect distance sampling is widely used to estimate population densities using distances of observed targets from transect lines to model detectability. When the target taxa are high density, the frequent measuring of distances may make the method
Kathryn Knights +3 more
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Line Transect Sampling in Small Regions
Biometrics, 2001 This article develops an approach to estimating population abundance from line transect surveys that uses a calibration survey to estimate the detection function, which is then employed as a weight function in constructing the abundance estimate. Nonparametric methods of estimating the detection function via local regression and via a kernel density ...
Melville, G, Welsh, Alan
openaire +6 more sources
Cogent EngineeringThe line transect survey method is commonly used to estimate the population size. However, recent developments in this field have tended to prefer practical mathematical models for this purpose.
Sana Kanwal +4 more
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The "Tracked Roaming Transect" and distance sampling methods increase the efficiency of underwater visual censuses. [PDF]
PLoS ONE, 2018 Underwater visual census (UVC) is the most common approach for estimating diversity, abundance and size of reef fishes in shallow and clear waters. Abundance estimation through UVC is particularly problematic in species occurring at low densities and/or ...
Alejo J Irigoyen +5 more
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Mark-recapture estimators for dual frame population size of prominent nesting structures: the effect of uncertain detection probability [PDF]
, 2005 The combined mark-recapture and line transect sampling methodology proposed by Alpizar- Jara and Pollock [Journal of Environmental and Ecological Statistics, 3(4), 311–327, 1996; In Marine Mammal Survey and Assessment Methods Symposium. G.W. Garner, S.C.
Alpizar-Jara, R. +2 more
core +1 more source
Integrated Environmental Assessment and Management, EarlyView., 2023 Abstract In the Lake Koocanusa‐Kootenai River system (Montana, USA and British Columbia, Canada), selenium (Se) contamination has become an international concern and is suspected to contribute to the observed burbot (Lota lota) population collapse. Due to our limited ability to sample burbot in Lake Koocanusa for monitoring studies, we used a reference
Stephanie D. Graves +6 more
wiley +1 more source
A comparison of four different methods to estimate population size of Alpine marmot (Marmota marmota) [PDF]
, 2017 Obtaining reliable information on animal abundance in mountainous landscapes is challenging. Highly heterogeneous habitats tend to reduce detection probabilities, and the three-dimensional, rugged nature of the terrain poses severe limits to the ...
Bertolini, Matteo +4 more
core +1 more source
Improving aquatic warbler population assessments by accounting for imperfect detection.
PLoS ONE, 2014 Monitoring programs designed to assess changes in population size over time need to account for imperfect detection and provide estimates of precision around annual abundance estimates.
Steffen Oppel +3 more
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A hierarchical modeling framework for multiple observer transect surveys. [PDF]
PLoS ONE, 2012 Ecologists often use multiple observer transect surveys to census animal populations. In addition to animal counts, these surveys produce sequences of detections and non-detections for each observer. When combined with additional data (i.e.
Paul B Conn +2 more
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Zoologia (Curitiba), 2018 The spotted paca, Cuniculus paca (Linnaeus, 1766), is a Neotropical, opportunistic, frugivorous caviomorph rodent, that inhabits primarily broadleaf forests. We aimed to provide the first estimates of density of C.
Átilla C. Ferreguetti +2 more
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