I am designing a DNA CMR study for bears based on a 3x3 cluster of traps, with 2 km between traps (i.e., inter-trap distance) and 16 km between clusters (i.e., inter-cluster distance). The population I want to sample is centered on a National Wildlife Refuge but it spills over onto private land, with decreasing bear density as you get further from the refuge. I don't want to have the same sampling intensity in the outlying areas because of the labor involved in setting up traps. My question is whether I can use the 16 km inter-cluster distance in the NWR but gradually increase it (keeping the inter-trap dimensions the same) as I get further and further from the refuge without introducing a bias? I intend to run this scenario in secrdesign but wanted to get some opinions first. Thanks!!!
Joe