Results 21 to 30 of about 485,382 (284)
Avian Conservation and Ecology, 2018 Computer-automated image analysis techniques can save time and resources for detecting and counting birds in aerial imagery. Sophisticated object-based image analysis (OBIA) software is now widely available and has proven effective for various ...
Dominique Chabot +2 more
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Considering sampling bias in close‐kin mark–recapture abundance estimates of Atlantic salmon
Ecology and Evolution, 2021 Genetic methods for the estimation of population size can be powerful alternatives to conventional methods. Close‐kin mark–recapture (CKMR) is based on the principles of conventional mark–recapture, but instead of being physically marked, individuals are
Sebastian Wacker +6 more
doaj +1 more source
Global abundance estimates for 9,700 bird species [PDF]
Proceedings of the National Academy of Sciences, 2021 Significance For the fields of ecology, evolutionary biology, and conservation, abundance estimates of organisms are essential. Quantifying abundance, however, is difficult and time consuming. Using a data integration approach integrating expert-derived abundance estimates and global citizen science data, we estimate the global population of ...
Corey T. Callaghan +2 more
openaire +2 more sources
Joint Bayesian endmember extraction and linear unmixing for hyperspectral imagery [PDF]
, 2009 This paper studies a fully Bayesian algorithm for endmember extraction and abundance estimation for hyperspectral imagery. Each pixel of the hyperspectral image is decomposed as a linear combination of pure endmember spectra following the linear mixing ...
Alfred O. Hero +5 more
core +9 more sources
Arctic Science, 2018 The Southern Hudson Bay polar bear (Ursus maritimus Phipps, 1774) subpopulation is considered stable, but conflicting evidence lends uncertainty to that designation.
Martyn E. Obbard +5 more
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Using digital recordings and sonogram analysis to obtain counts of yellow rails
Wildlife Society Bulletin, 2016 Autonomous recording units (ARUs) are emerging as a useful technology for the study and monitoring of animals that produce vocalizations. During summer and fall of 2013, we performed a series of experiments aimed at developing sampling protocols to count
Kiel L. Drake +3 more
doaj +1 more source
Is scuba sampling a relevant method to study microhabitat in lakes? Examples and comparisons for three European species [PDF]
, 2001 We compared fish microhabitat use patterns in the littoral zone of a lake using a new direct method (i.e. Point Abundance Sampling by Scuba, PASS) and the widely used Point Abundance Sampling by Electrofishing technique (PASE).
Brosse, Sébastien +3 more
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California Fish and Wildlife Journal, 2022 Historically, aerial surveys have been used widely to monitor abundance of large mammals in the western United States. In California, such surveys have typically served as minimum count indices rather than true abundance estimates. Here, we evaluated the
Thomas J. Batter +3 more
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Avian Conservation and Ecology, 2017 Autonomous recording units (ARUs) show promise for improving the spatial and temporal coverage of biodiversity monitoring programs, and for improving the resolution with which the behaviors of animals can be monitored on small spatial scales.
Richard W. Hedley, Yiwei Huang, Kung Yao
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Chemical abundances of LINER galaxies – nitrogen abundance estimations
Monthly Notices of the Royal Astronomical SocietyABSTRACT In this work, we investigated the nitrogen and oxygen abundances in a sample of galaxies with Low Ionization Nuclear Emission Regions (LINERs) in their nucleus. Optical spectroscopic data (3600 – 10 000 Å) of 40 LINERs from the Mapping Nearby Galaxies (MaNGAs) survey were considered.
C B Oliveira +7 more
openaire +3 more sources