sparrowDf {Rdistance} | R Documentation |
Brewer's Sparrow detection data frame in Rdistance >4.0.0 format.
Description
Detection data from line transect surveys for Brewer's sparrow on 72 transects located on a 4105 km^2 study area in central Wyoming collected by Dr. Jason Carlisle as part of his graduate work in the Wyoming Cooperative Fish & Wildlife Research Unit in 2012. Each transect was 500 meters long.
Format
A rowwise tibble containing 72 rows and 9 columns, one of which
is nested data frame of detections. Each row represents
one transect. The embedded data frame in column detections
contains the detections made on the transect represented on that row.
Column descriptions:
-
siteID
: Factor (72 levels), the transect identifier for that row of the data frame. -
length
: The length, in meters [m], of each transect. -
observer
: Identity of the observer who surveyed the transect. -
bare
: The mean bare ground cover (%) within 100 [m] of the transect. -
herb
: The mean herbaceous cover (%) within 100 [m] of the transect. -
shrub
: The mean shrub cover (%) within 100 [m] of the transect. -
height
: The mean shrub height [cm] within 100 [m] of the transect. -
shrubclass
: Shrub class factor. Either "Low"" when shrub cover is < 10%, or "High" if cover >= 10%.
The embedded data frame in column detections
contains the following
variables:
-
groupsize
: The number of individuals in the detected group. -
sightdist
: Distance [m] from observer to the detected group. -
sightangle
: Angle [degrees] from the transect line to the detected group. Not bearing. Range 0 [degrees] to 90 [degrees]. -
dist
: Perpendicular, off-transect distance [m], from the transect to the detected group. This is the distance used in analysis. Calculated usingperpDists
.
Source
The Brewer's sparrow data are a subset of data collected by Jason Carlisle and various field technicians for his Ph.D. from the Department of Ecology, University of Wyoming, in 2017. This portion of Jason's work was funded by the Wyoming Game and Fish Department through agreements with the University of Wyoming's Cooperative Fish & Wildlife Research Unit (2012).
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.
Carlisle, J. D., and A. D. Chalfoun. 2020. The abundance of Greater Sage-Grouse as a proxy for the abundance of sagebrush-associated songbirds in Wyoming, USA. Avian Conservation and Ecology 15(2):16. doi:10.5751/ACE-01702-150216
See Also
sparrowSiteData
, sparrowDetectionData
,
RdistDf
Examples
## Not run:
# The following code generated 'sparrowDf'
data(sparrowDetectionData)
data(sparrowSiteData)
sparrowDf <- RdistDf(transectDf = sparrowSiteData
, detectionDf = sparrowDetectionData
, by = "siteID"
, pointSurvey = FALSE
, .effortCol = "length"
)
## End(Not run)
data(sparrowDf)
tidyr::unnest(sparrowDf, detections) # only non-zero transects
Rdistance::unnest(sparrowDf) # with zero transects at the bottom
summary(sparrowDf,
formula = dist ~ groupsize(groupsize)
)