Abundance estimation
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REVIEW: Wildlife camera trapping: a review and recommendations for linking surveys to ecological processes Open
Summary Reliable assessment of animal populations is a long‐standing challenge in wildlife ecology. Technological advances have led to widespread adoption of camera traps ( CT s) to survey wildlife distribution, abundance and behaviour. As…
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Distance sampling with camera traps Open
Summary Reliable estimates of animal density and abundance are essential for effective wildlife conservation and management. Camera trapping has proven efficient for sampling multiple species, but statistical estimators of density from cam…
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Three novel methods to estimate abundance of unmarked animals using remote cameras Open
Abundance and density estimates are central to the field of ecology and are an important component of wildlife management. While many methods exist to estimate abundance from individually identifiable animals, it is much more difficult to …
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State–space mark–recapture estimates reveal a recent decline in abundance of North Atlantic right whales Open
North Atlantic right whales ( Eubalaena glacialis Müller 1776) present an interesting problem for abundance and trend estimation in marine wildlife conservation. They are long lived, individually identifiable, highly mobile, and one of the…
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A simple method for estimating the effective detection distance of camera traps Open
Estimates of animal abundance are essential for understanding animal ecology. Camera traps can be used to estimate the abundance of terrestrial mammals, including elusive species, provided that the sensitivity of the sensor, estimated as t…
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Assessing use of and reaction to unmanned aerial systems in gray and harbor seals during breeding and molt in the UK Open
Wildlife biology applications of unmanned aerial systems (UAS) are extensive. Survey, identification, and measurement using UAS equipped with appropriate sensors can now be added to the suite of techniques available for monitoring animals …
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Estimating the Abundance of Marine Mammal Populations Open
Motivated by the need to estimate the abundance of marine mammal populations to inform conservation assessments, especially relating to fishery bycatch, this paper provides background on abundance estimation and reviews the various methods…
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Detection errors in wildlife abundance estimates from Unmanned Aerial Systems (<span>UAS</span>) surveys: Synthesis, solutions, and challenges Open
Unmanned aerial systems ( UAS ) are emerging as an accessible and versatile tool for ecologists, promising to revolutionize the way abundance and distribution data are obtained in wildlife studies. Establishment of UAS as an efficient and …
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Hyperspectral Image Unmixing With Endmember Bundles and Group Sparsity Inducing Mixed Norms Open
Hyperspectral images provide much more information than conventional imaging techniques, allowing a precise identification of the materials in the observed scene, but because of the limited spatial resolution, the observations are usually …
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Identification errors in camera-trap studies result in systematic population overestimation Open
Reliable assessments of animal abundance are key for successful conservation of endangered species. For elusive animals with individually-unique markings, camera-trap surveys are a benchmark standard for estimating local and global populat…
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A hierarchical distance sampling model to estimate abundance and covariate associations of species and communities Open
Summary Distance sampling is a common survey method in wildlife studies, because it allows accounting for imperfect detection. The framework has been extended to hierarchical distance sampling (HDS), which accommodates the modelling of abu…
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Methodology matters when estimating deer abundance: a global systematic review and recommendations for improvements Open
Deer (Cervidae) are key components of many ecosystems and estimating deer abundance or density is important to understanding these roles. Many field methods have been used to estimate deer abundance and density, but the factors determining…
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A Review of Wildlife Abundance Estimation Models: Comparison of Models for Correct Application Open
In this review, the various models to estimate wildlife abundance are organized for promoting the correct application of them in animal ecology. If individuals of the target wildlife are distinguishable, the capture-recapture (CR) model an…
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Mark-Recapture and Mark-Resight Methods for Estimating Abundance with Remote Cameras: A Carnivore Case Study Open
Abundance estimation of carnivore populations is difficult and has prompted the use of non-invasive detection methods, such as remotely-triggered cameras, to collect data. To analyze photo data, studies focusing on carnivores with unique p…
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Estimating abundance of a cryptic social carnivore using spatially explicit capture–recapture Open
Estimating population abundance of wolves ( Canis lupus ) in densely forested landscapes is challenging because reduced visibility lowers the success of methods such as aerial surveys and enumeration of group size using radiotelemetry. How…
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The Effect of Animal Movement on Line Transect Estimates of Abundance Open
Line transect sampling is a distance sampling method for estimating the abundance of wild animal populations. One key assumption of this method is that all animals are detected at their initial location. Animal movement independent of the …
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Hyperspectral Unmixing via Low-Rank Representation with Space Consistency Constraint and Spectral Library Pruning Open
Spectral unmixing is a popular technique for hyperspectral data interpretation. It focuses on estimating the abundance of pure spectral signature (called as endmembers) in each observed image signature. However, the identification of the e…
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Best practices to account for capture probability and viewable area in camera‐based abundance estimation Open
A suite of recently developed statistical methods to estimate the abundance and density of unmarked animals from camera traps require accurate estimates of the area sampled by each camera. Although viewshed area is fundamental to achieving…
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Population abundance estimation with heterogeneous encounter probabilities using numerical integration Open
Estimation of population abundance is a common problem in wildlife ecology and management. Capture‐mark‐reencounter (CMR) methods using marked animals are a standard approach, particularly in recent history with the development of innovati…
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Assessment of the Bering-Chukchi-Beaufort Seas stock of bowhead whales using Bayesian model averaging Open
Bayesian estimation methods are used to fit an age- and sex-structured population model to available data on abundance and stageproportions (i.e. calves/mature animals in the population) for the Bering-Chukchi-Beaufort Seas stock of bowhea…
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Estimating animal abundance and effort–precision relationship with camera trap distance sampling Open
Effective monitoring methods are needed for assessing the state of biodiversity and detecting population trends. The popularity of camera trapping in wildlife surveys continues to increase as they are able to detect species in remote and d…
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Practical Bias Correction in Aerial Surveys of Large Mammals: Validation of Hybrid Double-Observer with Sightability Method against Known Abundance of Feral Horse (Equus caballus) Populations Open
Reliably estimating wildlife abundance is fundamental to effective management. Aerial surveys are one of the only spatially robust tools for estimating large mammal populations, but statistical sampling methods are required to address dete…
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Estimates of abundance south of 60°S for cetacean species sighted frequently on the 1978/79 to 1997/98 IWC/IDCR-SOWER sighting surveys Open
Estimates of abundance are calculated for six cetacean species in the Southern Ocean south of 60° in the austral summer, using the IWC database estimation package (DESS). The sightings data in DESS were collected during the 1978/79 to 1997…
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A semi‐automated camera trap distance sampling approach for population density estimation Open
Camera traps have become important tools for the monitoring of animal populations. However, the study‐specific estimation of animal detection probabilities is key if unbiased abundance estimates of unmarked species are to be obtained. Sinc…
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Horvitz–Thompson whale abundance estimation adjusting for uncertain recapture, temporal availability variation, and intermittent effort Open
A Horvitz–Thompson‐type estimator is introduced to estimate total abundance of the Bering–Chukchi–Beaufort Seas population of bowhead whales using combined visual and acoustic location data. The estimator divides sightings counts by three …
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Guidance on estimation of abundance and density data of wild ruminant population: methods, challenges, possibilities Open
The methods for estimating relative abundance and density in wild ruminant species are reviewed and insights on how to obtain reliable estimations by using those methods are provided. Eighteenmethods used in nineteenwild ruminant species w…
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Hyperspectral Unmixing via Double Abundance Characteristics Constraints Based NMF Open
Hyperspectral unmixing aims to obtain the hidden constituent materials and the corresponding fractional abundances from mixed pixels, and is an important technique for hyperspectral image (HSI) analysis. In this paper, two characteristics …
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Integrated modeling to estimate population size and composition of mule deer Open
Estimating population size, age composition, and sex ratio of mule deer ( Odocoileus hemionus ) is important to conservation and managed hunting of this species in the western United States. Increasingly, wildlife agencies are estimating a…
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Double Reweighted Sparse Regression and Graph Regularization for Hyperspectral Unmixing Open
Hyperspectral unmixing, aiming to estimate the fractional abundances of pure spectral signatures in each mixed pixel, has attracted considerable attention in analyzing hyperspectral images. Plenty of sparse unmixing methods have been propo…
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Joint Local Abundance Sparse Unmixing for Hyperspectral Images Open
Sparse unmixing is widely used for hyperspectral imagery to estimate the optimal fraction (abundance) of materials contained in mixed pixels (endmembers) of a hyperspectral scene, by considering the abundance sparsity. This abundance has a…