I am trying to calculate the volume of intersection for the utilization distribution of many animals. I have estimated their UDs using move::brownian.bridge.dyn() for each animal then used getVolumeUD() which gives me the UD as a RasterLayer.
mod1 <- brownian.bridge.dyn(indiv, raster = xy, location.error = 10) #using default margin and window size
mod1.ud <- getVolumeUD(mod1)
To calculate the overlap I am trying to use adehabitatHR::kerneloverlapHR which requires the UDs to be an estUDm type object. I can make the individual UD into an estUD object
mod1.px <- as(mod1.ud, "SpatialPixelsDataFrame")
mod1.estud <- new("estUD",mod1.px)
But cannot figure out how to combine those into one estUDm. I've tried
all.ud <- c(mod1.estud, mod2.estud, ...)
class(all.ud) <- "estUDm"
vi <- kerneloverlapHR(all.ud, meth="VI", percent=95, conditional=TRUE)
Error in kerneloverlaphr(all.ud) : x should not be a volume under UD
I have also tried to make the estUDm object by stacking the UD rasters.
Any ideas? I'm open to a different method to calculate the volume intersection as well, just haven't found another method.
Thank you!
