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Hello,

I am working on estimating density for a lagomorph and am using polygon detectors to do so. I have a couple questions:

-To get models to converge well, I needed to use an over-sized buffer (500m vs 100-200 that would fit the species better). When I used other detector types in the past, the size of the buffer did not have a strong influence on the density estimate. Should that be the case here as well?

-The reason that I ask is that when I multiply density by the study area we sampled tot get N, the estimates that I obtain are lower than the number of individuals we detected. I am wondering how to best resolve this.

Thank you!

Of course, I do not know specifically why you are having trouble. The second issue is a consequence of the first, and not surprising (the model is proposing that some detected animals have centres outside the study area). I suggest you upgrade to 2.10.2 and try one of the 'hazard' detection functions 14-18 (e.g. detectfn = 'HHN'). Let us know how you get on.
Murray