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As was mentioned above, managers can decide where to sample, but our recommendations are generally
to sample in cover types and areas which there is some evidence of historical lynx occurrence. Maps of
broad cover-types associated with historic lynx occurrence are available for the contiguous US. These
cover-type maps, or local vegetation coverage, can serve as a guide for determining priority of survey
efforts. We would caution that, early in the process, deciding a priori that an area cannot support lynx
without detailed local knowledge, is not without risk. If grids are designed as a representative sample of
a particular cover type, sampling within this cover type provides no information about any other cover
type. There will always be this trade-off: tight stratification rules will presumably increase the efficacy,
but they limit the inference. Additionally, this grid-based approach works best and is most efficient in
areas where cover types are reasonably contiguous.
Exactly how you resolve the relative importance of these two properties: efficacy vs inference, and hence
how you stratify your landscape prior to sampling, will largely be a function of local knowledge,
priorities, and vegetation patterns. Two examples may provide insight into this process. In the Superior
NF a question of primary importance is: Do we have any resident populations of lynx? To answer this
question, the Superior will be looking to place grids in those areas where they have the most recent
evidence of lynx occurrence and where the habitat appears to be most suitable. In the Okanogan NF, the
presence of lynx in the area studied by Koehler and Brittell is not in question. The Okanogan, therefore
is placing grids in areas where they have some information that lynx occur, and would like to gather
more data concerning these lynx. They are not, therefore, necessarily placing the surveys in the "best"
areas, as is the Superior, but they are still only surveying in-and-adjacent-to cool wet forest types.
