dsdata: Distance sampling workshop data

#' Sika deer pellet data from southern Scotland
#'
#' Because sika deer spend most of their time in woodland areas, abundance
#' estimates are based on pellet group counts.  Line transect methods were applied
#' to estimate deer pellet group density by geographic block.
#'
#' Data presented here are from the Peebleshire portion of the study described by 
#' Marques et al. (2001).
#'
#' @name sikadeer
#' @aliases sikadeer_units
#' @docType data
#' @format A data frame with 1923 rows and 11 variables.
#'   \tabular{ll}{  
#'     \code{Region.Label} \tab stratum labels \cr
#'     \code{Area} \tab size (ha) of each stratum \cr
#'     \code{Sample.Label} \tab transect labels \cr
#'     \code{Defecation.rate} \tab rate of dung production per individual per day \cr
#'     \code{Defecation.rate.SE} \tab variability in defecation rate \cr
#'     \code{Decay.rate} \tab time (days) for dung to become undetectable \cr
#'     \code{Decay.rate.SE} \tab variability in decay rate \cr
#'     \code{Effort} \tab transect length (km) \cr
#'     \code{object} \tab object ID \cr
#'     \code{distance} \tab perpendicular distance (cm) \cr
#'     \code{Study.Area} \tab study area name \cr
#'   }
#' @references Marques, F.F.C., S.T. Buckland, D. Goffin, C.E. Dixon, D.L. Borchers, B.A. Mayle, and A.J. Peace. (2001).
#'  Estimating deer abundance from line transect surveys of dung: 
#'  sika deer in southern Scotland. Journal of Applied Ecology 38 (2): 349–363.
#'   https://doi.org/10.1046/j.1365-2664.2001.00584.x
#' @keywords datasets
NULL