Data
The American black bear Ursus americanus was arbitrarily chosen to illustrate the method because it was expected to have a large, well-sampled range. Data were drawn from the Global Biodiversity Information Facility (GBIF) using the occ_data function in R library rgbif (Chamberlain et al. 2020) on 2 September 2020. After processing the data with the st_polygon and st_sfcfunctions in the R library sf (Pebesma 2018), convex hull areas were computed using st_area .
Monte Carlo simulations were used to compare the four methods. Data were placed randomly within ranges having simple geometrical shapes. Four sets of simulations were implemented. (1) Comparisons of all four methods using five points randomly drawn from within a circle in each trial. (2) Comparisons with 20 points drawn. (3) Comparisons with 20 points drawn from a circle and 80% of the data points in the right-hand side of the shape randomly removed. (4) Trials using six different shapes, with 10 points being drawn during each trial and only the mosaic area method being applied in most cases.