How to calculate 3D overlap index of Brownian bridge movement models in adehabitatHR

Hi all,

I wish to look at home range overlap using a 3D overlap index (preferably UDOI) and using utilisation distributions generated by brownian bridge movement models.

The adehabitatHR function kerneloverlaphr acts on estUDm objects to calculate overlaps.

Is there a way to ?stack? the utilisation distributions calculated from the BBMM function brownian.bridge into a single estUDm object that can then be handled by kerneloverlaphr?

Alternatively, is there another function to measure overlap of a brownian bridge generated utilisation distributions?

Thank you in advance,

Kasim

## Example code:

require(adehabitatHR)
require(BBMM)

data(locations)  ## Example dataset

BBMM <- brownian.bridge(x=locations$x, y=locations$y,
                        time.lag=locations$time.lag[-1], location.error=20,
                        cell.size=50)

locations2 <- locations
locations2$x <-locations2$x + 5000 # To create example overlapping UD

BBMM2 <- brownian.bridge(x=locations2$x, y=locations2$y,
                        time.lag=locations2$time.lag[-1], location.error=20,
                        cell.size=50)


x <- # function to stack the bbmm output as a single estUDm object that can be handled by kerneloverlaphr

kerneloverlaphr(x, method='UDOI')