Quries Regarding Things to check : State-space extent

[Aditya Malgaonkar]

So among the things to check there is : -  State-space extent: For spatial models, check the detection function plot and the detection probability for the smallest trap to state space edge distance. The detection probability for any animals with home ranges outside must be very small.

What does  "the detection probability for the smallest trap to state space edge distance." mean and how to make sure of it ?