Generalizing animal distributions adjacent to habitat boundaries is problematic. You may wish to consider functions available in adehabitatHR for the biased random bridge and classic kernel utilization distribution algorithms that offer an elegant solution to this problem. I have found these appealing, yet not applicable to my study species due to coastline compexities (islands that are small relative to the kernel smoothing factor and coastal segmements that form angles too accute for the functions to handle). I resorted to excluding non-habitat from the utilization distribution. Here is the post thread http://r-sig-geo.2731867.n2.nabble.com/Walruses-and-adehabitatHR-class-estUDm-exclusion-of-non-habitat-pixels-and-summary-over-all-animals-tp6497315p6497315.html ...adehabitatHR: class estUDm exclusion of non-habitat pixels... whereby r-sig-geo contributors provided a solution for this exclusion.
HTH - ----- Tony Fischbach, Wildlife Biologist Walrus Research Program Alaska Science Center U.S. Geological Survey 4210 University Drive Anchorage, AK 99508-4650 afischb...@usgs.gov http://alaska.usgs.gov/science/biology/walrus -- View this message in context: http://r-sig-geo.2731867.n2.nabble.com/Extracting-minimum-convex-polygons-of-species-distributions-tp7375692p7375974.html Sent from the R-sig-geo mailing list archive at Nabble.com. _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo