[AniMov] GRASS Addons for the estimation of home ranges

[Clément Calenge]

Dear All,

I programmed three new add-ons for the GRASS software, and thanks to the 
kind help of Markus Neteler, they are now available on the GRASS Addons 
repository. These addons allow to estimate the home range of animals 
monitored using radio-tracking, GPS, Argos, etc. They implement three 
main home range estimation methods provided by the package adehabitat 
for the R software:

* v.adehabitat.clusthr: this addon allows the estimation of the home 
range by single linkage cluster analysis, using the methodology of
    Kenward R.E. et al. (2001; Ecology). This method has been 
"translated" for GRASS from the R function "clusthr" in the R package 
adehabitat.

* v.adehabitat.mcp: this addon estimates the minimum convex polygon home 
range (Mohr, C.O. 1947. The American Midland Naturalist). This function 
is just a slight modification of the module v.hull of Andrea Aime 
(aaime at libero.it).

* v.adehabitat.kernelUD: this addon allows the estimation of the kernel 
utilization distribution and home ranges, following the guidelines 
provided in Worton (1995; Journal of Wildlife Management). This module 
heavily relies on the code written by Stefano Menegon for his module 
v.kernel. It has just been extended to allow the LSCV and ad hoc 
estimation of the smoothing parameter, and the computation of the volume 
under the UD for home range estimation. The only difference with the 
function kernelUD from the R package adehabitat is related to the LSCV 
method: because the minimization of the MISE requires numerical methods, 
the smoothing parameter found by v.adehabitat.kernelUD differ slightly 
from those returned by the function kernelUD in adehabitat (the 
correlation between the two is often greater than 0.99, pers.obs.).

Happy testing,

Clément Calenge

-- 
Clément CALENGE
Office national de la chasse et de la faune sauvage
Saint Benoist - 78610 Auffargis
tel. (33) 01.30.46.54.14