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Rdistance (version 2.1.3)

thrasherDetectionData: Sage Thrasher detection data (point-transect survey)

Rdistance contains four example datasets: two collected using a line-transect survey (i.e., sparrowDetectionData and sparrowSiteData) and two collected using a point-transect (sometimes called a point count) survey (i.e., thrasherDetectionData and thrasherSiteData). These datasets demonstrate the type and format of input data required by Rdistance to estimate a detection function and abundance from distance sampling data collected by surveying line transects or point transects. They also allow the user to step through the tutorials described in the package vignettes. Only the detection data is needed to fit a detection function (if there are no covariates in the detection function; see dfuncEstim), but both detection and the additional site data are needed to estimate abundance (or to include site-level covariates in the detection function; see abundEstim).

Line transect (sparrow) data come from 72 transects, each 500 meters long, surveyed for Brewer's Sparrows by the Wyoming Cooperative Fish & Wildlife Research Unit in 2012.

Point transect (thrasher) data come from 120 points surveyed for Sage Thrashers by the Wyoming Cooperative Fish & Wildlife Research Unit in 2013.

See the package vignettes for Rdistance tutorials using these datasets.

Description

Sage Thrasher detection data (point-transect survey)

Rdistance contains four example datasets: two collected using a line-transect survey (i.e., sparrowDetectionData and sparrowSiteData) and two collected using a point-transect (sometimes called a point count) survey (i.e., thrasherDetectionData and thrasherSiteData). These datasets demonstrate the type and format of input data required by Rdistance to estimate a detection function and abundance from distance sampling data collected by surveying line transects or point transects. They also allow the user to step through the tutorials described in the package vignettes. Only the detection data is needed to fit a detection function (if there are no covariates in the detection function; see dfuncEstim), but both detection and the additional site data are needed to estimate abundance (or to include site-level covariates in the detection function; see abundEstim).

Line transect (sparrow) data come from 72 transects, each 500 meters long, surveyed for Brewer's Sparrows by the Wyoming Cooperative Fish & Wildlife Research Unit in 2012.

Point transect (thrasher) data come from 120 points surveyed for Sage Thrashers by the Wyoming Cooperative Fish & Wildlife Research Unit in 2013.

See the package vignettes for Rdistance tutorials using these datasets.

Arguments

Format

A data.frame containing 193 rows and 3 columns. Each row represents a detected group of thrashers. Column descriptions:

  1. siteID: Factor (120 levels), the site or point where the detection was made.

  2. groupsize: Number, the number of individuals within the detected group.

  3. dist: Number, the radial distance (m) from the transect to the detected group. This is the distance used in analysis.

References

Carlisle, J.D. 2017. The effect of sage-grouse conservation on wildlife species of concern: implications for the umbrella species concept. Dissertation. University of Wyoming, Laramie, Wyoming, USA.

See Also

thrasherSiteData