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We used the United States National Grid to develop a sampling grid for monitoring programs in the Great Plains Landscape Conservation Cooperative, delineated by Bird Conservation Regions 18 and 19. Landscape Conservation Cooperatives are science based partnerships with the goal to inform and guide conservation at regional landscape levels. Developing a standardized sampling grid for a LCC is a new endeavor and is designed to reduce program costs, avoid repetition in sampling, and increase efficiency in monitoring programs. This is possible because the grid’s nationwide coverage, uniform starting point, and scalability allow researchers to expand their monitoring programs from a small, local level to a regional or...
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R code that takes in the nest capture history data (chdata.csv), reformats it for model fitting in Program Mark via the R package RMark. A series of models of increasing complexity are fit and compared using AIC. Output is written to text files for each model but is generally not used or saved. Code can be run to generate model results and R workspaces/ object to inspect parameter estimates. The primary purpose of this code is to explore model structures for predicting detection and as an attempt to reproduce historically used parameter estimates in past nest plot reports (e.g., Fischer et al. 2017 and earlier). Results from ‘Model 7’ are most similar to detection estimates used in the past.
Categories: Data, Software; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: ANIMALS/VERTEBRATES, ANIMALS/VERTEBRATES, ANIMALS/VERTEBRATES, BIOLOGICAL CLASSIFICATION, BIOLOGICAL CLASSIFICATION, All tags...
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R code that takes in the nest capture history data (chdata.csv), reformats it for model fitting in the Bayesian MCMC software JAGS via the R package jagsUI. Various generalized linear mixed models are fit using a Huggins two occasion capture history model structure as in Program Mark. A series of models of increasing complexity are fit and compared using DIC. Model text is written to text files for each model but is generally not used or saved. Posteriors are saved as Rworkspaces or written to text files for use in population estimation (nostpop.R). Code can be run to generate model results and R workspaces/objects to inspect parameter estimates. The primary purpose of this code is to compare various mixed model...
Categories: Data, Software; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: ANIMALS/VERTEBRATES, ANIMALS/VERTEBRATES, ANIMALS/VERTEBRATES, BIOLOGICAL CLASSIFICATION, BIOLOGICAL CLASSIFICATION, All tags...
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This multi-layer GeoPackage contains the Alaska Arctic Coastal Plain Aerial Breeding Pair Survey design transects from 2007 to present. The original transects were created as shapefiles and imported to this SQLite database. Transects were saved as individual polylines named according to the year they were created (e.g., “main.ACP_2007_Trans,” “main.ACP_2008_Trans,” “main.ACP_2009_Trans,” etc.). These aerial transects were developed systematically from randomly-selected start points and created along constant lines of latitude. The inter-transect spacing in the low, medium, high, and very-high density strata varies so that areas with higher waterfowl density are surveyed more intensively. The current four-year rotating...
Lack of complete snow cover for the past 3 winters in southwestern Alaska has forced agencies to postpone conducting moose surveys due to the likelihood of underestimating the population. For most regions of Alaska, the variation in moose sightability during suboptimal conditions has not yet been quantified. Because scientists are predicting less snowfall in this region over the long term, research was initiated to estimate sightability correction factors (SCFc) to apply to abundance estimates.
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In 2019 a pilot study was conducted to determine the feasibility of using distance sampling to estimate density and population size of goose and eider nests on the Yukon-Kuskokwim Delta (YKD). Distance sampling (Buckland et al. 2001) is a common and well-understood method to estimate wildlife population size or density, especially for sparse and hard-to-detect populations. A main advantage of distance sampling is that it accounts for imperfect detection and gives precise estimates for a given level of effort relative to other methods. The objectives for the pilot project in 2019 was to (1) determine if distance sampling is feasible on the YKD, (2) determine what aspects of the field protocol need to be changed or...
Lack of complete snow cover for the past 3 winters in southwestern Alaska has forced agencies to postpone moose surveys due to the likelihood of underestimating the population/lack of comparability to previous surveys. Poor snow conditions lower the sightability of moose, yet, for most regions of Alaska, the variation in moose sightability during suboptimal conditions has not yet been quantified. Because scientists are predicting less snowfall in this region over the long term, we initiated research to estimate sightability correction factors (SCF_c) using radiocollared animals to apply to abundance estimates obtained via the GeoSpatial Population Estimator (GSPE) method. The Project Goal is to develop a model that...
Categories: Data, Project; Tags: 2016, Academics & scientific researchers, Academics & scientific researchers, CALIBRATION/VALIDATION, CALIBRATION/VALIDATION, All tags...
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The document reviews the theory of distance sampling, important assumptions, and case studies where distance sampling has been used. Reported in this document are results from some power analysis to guide design of a pilot study. This report became part of a Master’s thesis project and was used for development of a field protocol.
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This R code uses the nest card data (“Nest_Cards_1985_2019_QC.csv”), cumulative observer experience data (“cumnest.csv”), and the output from the detection model to produce nest population estimates for focal species or species groups. Model results used are the the maximum likelihood estimates and covariance matrix from Program Mark for “model 7” or from a Bayesian posterior distribution based on a generalized linear mixed model for detection with random effects for plot, year, and crew. Results from “model 7” are produced only to provide population estimates based on legacy methods as reported in past reports. For final estimates, results from the Bayesian posterior should be used. Result from either model cannot...
Categories: Data, Software; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: ANIMALS/VERTEBRATES, ANIMALS/VERTEBRATES, ANIMALS/VERTEBRATES, ANIMALS/VERTEBRATES, ANIMALS/VERTEBRATES, All tags...
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This document is a report on a project for a Masters student thesis to understand distance sampling to estimate eider and goose nest density. The abstract from the report is:The U.S. Fish and Wildlife Service currently conducts annual surveys to estimate bird nest abundanceon the Yukon-Kuskokwim Delta, Alaska. The current method involves intensive searching on large plots withthe goal of finding every nest on the plot. Distance sampling is a well-established transect-based methodto estimate density or abundance that accounts for imperfect detection of objects. It relies on estimatingthe probability of detecting an object given its distance from the transect line, or the detection function.Simulations were done using...
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We used the United States National Grid to develop a sampling grid for monitoring programs in the Great Plains Landscape Conservation Cooperative, delineated by Bird Conservation Regions 18 and 19. Landscape Conservation Cooperatives are science based partnerships with the goal to inform and guide conservation at regional landscape levels. Developing a standardized sampling grid for a LCC is a new endeavor and is designed to reduce program costs, avoid repetition in sampling, and increase efficiency in monitoring programs. This is possible because the grid’s nationwide coverage, uniform starting point, and scalability allow researchers to expand their monitoring programs from a small, local level to a regional or...
Lack of complete snow cover for the past 3 winters in southwestern Alaska has forced agencies to postpone conducting moose surveys due to the likelihood of underestimating the population/lack of comparability to previous surveys. Poor snow conditions are known to lower the sightability of moose, yet, for most regions of Alaska, the variation in moose sightability during suboptimal conditions has not yet been quantified. Because scientists are predicting less snowfall in this region over the long term, research was initiated to estimate sightability correction factors (SCFc) to apply to abundance estimates.


    map background search result map search result map Integrated monitoring within BCR’s: Creating a wildlife monitoring grid for the GPLCC Project Summary: Integrated monitoring within BCR’s: Creating a wildlife monitoring grid for the GPLCC Final Report: Integrated monitoring within BCR’s: Creating a wildlife monitoring grid for the GPLCC Alaska Arctic Coastal Plain Aerial Breeding Pair Survey Design Transect Geodata Alaska Yukon Delta Nest Distance Sampling Pilot Project Alaska Yukon Delta Line Transect Distance Sampling to Estimate Nest Density on the Yukon-Kuskokwim Delta Alaska Yukon Delta Detection Model Fitting Code Using R and RMark Alaska Yukon Delta Nest Plot Survey Detection Model Fitting Code Using R and JAGS Alaska Yukon Delta Nest Population Estimation Code Using R Simulating distance sampling to estimate nest abundance at Alaska Yukon-Kuskokwim Delta Alaska Yukon Delta Nest Distance Sampling Pilot Project Simulating distance sampling to estimate nest abundance at Alaska Yukon-Kuskokwim Delta Alaska Yukon Delta Line Transect Distance Sampling to Estimate Nest Density on the Yukon-Kuskokwim Delta Alaska Yukon Delta Detection Model Fitting Code Using R and RMark Alaska Yukon Delta Nest Plot Survey Detection Model Fitting Code Using R and JAGS Alaska Yukon Delta Nest Population Estimation Code Using R Alaska Arctic Coastal Plain Aerial Breeding Pair Survey Design Transect Geodata Integrated monitoring within BCR’s: Creating a wildlife monitoring grid for the GPLCC Project Summary: Integrated monitoring within BCR’s: Creating a wildlife monitoring grid for the GPLCC Final Report: Integrated monitoring within BCR’s: Creating a wildlife monitoring grid for the GPLCC