Occupancy estimation from unequal spatial patch sampling

[jlehmkuhl]

I am trying to help some colleagues analyze patch occupancy of Indian ungulates from pellet counts.

They recorded vegetation & pellet presence/absence of several species in 20 x 20 m quadrats (~1600 total) within ~100 patches. The number of quadrats within patches varied from 10 to over 50 depending on patch size. There were no repeat visits, just spatial replication.

I am an occupancy novice, but based on my reading I think I could use the spatial replication within patches in place of temporal replication (visits)? If yes, then how to code detection histories for patches when the number of quadrats varied so much? The detection histories would greatly vary in length among patches, unless padded with zeros.

[darryl]

Rather than padded out the detection histories with zeros, use periods (ie ".") so that they're all the same length.