From distance sampling to spatial capture–recapture

Distance Sampling

Spatial Distance Sampling Modeling of Cetaceans Observed from Platforms of Opportunity

In this paper I outline the standard methods of distance sampling and how they are used to obtain estimates of density and abundance for species of interest. I then develop these methods following the approach of Hedley (2000) whereby waiting distances between detections are modelled to produce a density map of the area of interest. In doing so Standard distance sampling, multi-covariate distan...

Spatial Sampling

In spatial sampling, we collect observations in a two-dimensional framework. Careful attention is paid to the quantity of the samples, dictated by the budget at hand, and the location of the samples. A sampling scheme is generally designed to maximize the probability of capturing the spatial variation of the variable under study. Once initial samples of the primary variable have been collected ...

Distance sampling analysis in unmarked

Distance sampling is a wildlife sampling technique used to estimate population size or density. Describing how density varies spatially is often of equal interest; however, conventional methods of analysis do not allow for explicit modeling of both density and detection probability. The function distsamp implements the multinomial-Poisson mixture model of Royle et al. (2004), which was develope...

Statistical Efficiency in Distance Sampling

Distance sampling is a technique for estimating the abundance of animals or other objects in a region, allowing for imperfect detection. This paper evaluates the statistical efficiency of the method when its assumptions are met, both theoretically and by simulation. The theoretical component of the paper is a derivation of the asymptotic variance penalty for the distance sampling estimator aris...