Wild horse aerial double observer survey analysis R script
November 22, 2019
This R file estimates horse abundance by analyzing data from simultaneous double-observer aerial surveys. The code follows analytical procedures established by Dr. Bruce Lubow, the statistician contracted for many years by Bureau of Land Management (BLM). Field data collection techniques are described in the Standard Operating Procedures (SOPs), which is a separate document.
Download the files "SDO_RMark_template.R" and "Example_data.csv" to the same directory. Open R and make this the working directory with File | Change dir.
Install the required packages "htmltools", "zoo", and "RMark". Make sure RMark is updated to the latest version if you already have it installed; earlier versions contained a bug that caused the script to crash.
Before running the script in R, expand the console window to best display results from tables in your web browser. Once you run the script, it pauses until you left click to move past figures. The pauses allow you time to inspect
graphs.
Tables are also saved in your working directory as .csv files. The R script outputs a text file (Report.txt) that is a rough first draft of the Memorandum, which is the report sent to BLM. All tables associated with the report are named "Report_TableX.csv"; the code also saves various other .csv tables with more detailed results, and a histogram of bootstrap results.
Download the files "SDO_RMark_template.R" and "Example_data.csv" to the same directory. Open R and make this the working directory with File | Change dir.
Install the required packages "htmltools", "zoo", and "RMark". Make sure RMark is updated to the latest version if you already have it installed; earlier versions contained a bug that caused the script to crash.
Before running the script in R, expand the console window to best display results from tables in your web browser. Once you run the script, it pauses until you left click to move past figures. The pauses allow you time to inspect
graphs.
Tables are also saved in your working directory as .csv files. The R script outputs a text file (Report.txt) that is a rough first draft of the Memorandum, which is the report sent to BLM. All tables associated with the report are named "Report_TableX.csv"; the code also saves various other .csv tables with more detailed results, and a histogram of bootstrap results.
Citation Information
Publication Year | 2019 |
---|---|
Title | Wild horse aerial double observer survey analysis R script |
DOI | 10.5066/P946MHTZ |
Authors | Lars S Ekernas |
Product Type | Software Release |
Record Source | USGS Asset Identifier Service (AIS) |
USGS Organization | Fort Collins Science Center |
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Standard operating procedures for wild horse and burro double-observer aerial surveys
The U.S. Geological Survey has been collaborating with the Bureau of Land Management to develop statistically reliable methods for wild horse and burro aerial survey data collection and analysis for more than a decade. In cooperation with Colorado State University, the U.S. Geological Survey tested several methods in herds with known abundance, resulting in two scientifically defensible...
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Paul C. Griffin, L. Stefan Ekernas, Kathryn A. Schoenecker, Bruce C. Lubow
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Standard operating procedures for wild horse and burro double-observer aerial surveys
The U.S. Geological Survey has been collaborating with the Bureau of Land Management to develop statistically reliable methods for wild horse and burro aerial survey data collection and analysis for more than a decade. In cooperation with Colorado State University, the U.S. Geological Survey tested several methods in herds with known abundance, resulting in two scientifically defensible...
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Paul C. Griffin, L. Stefan Ekernas, Kathryn A. Schoenecker, Bruce C. Lubow