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Reliability. Reliability is largely a product of effective and representative sampling, but there are
additional properties that a reliable survey protocol should have. It should be reliable in the sense that if
applied, it will produce interpretable results. At the finest scale (traditionally the scent station but, in our
design, the transect) if a lynx is present in the area, the probability of detection should be as constant as
possible. This allows the proportion of occurrences to infer use. At a larger scale, we want to reliably
state that, given a certain level of effort, we will have detections if lynx are present, and therefore a lack
of detections indicates a lack of lynx.
At the fine scale, placing scent stations 100 m apart and perpendicular to the major slope produces a
structure that will be encountered by lynx moving through the country and removes small-scale
differences associated with station placement. At a broader scale, the protocol requires placing no fewer
than 25 transects at a density of 1 transect per every 2 miles for a period of 2-4 weeks to ensure that an
area is adequately sampled.
Details
Broad decisions concerning where to sample
Decisions as to where to sample are based primarily on the interest of the managers. If grids (25+
transects) were placed randomly within a major cover type, the grids themselves would be a
representative sample of the cover type. A manager may, however, need information about lynx in a
specific area, and can place grids preferentially. In broken habitat, such as forested areas separated by
low elevation prairie, dry forest types or deciduous forests not thought to be lynx habitat, or lands which
have been converted to agriculture, the sampling does not need to conform to a rectangular grid. All
that is required is that the placement within the lynx habitat be at a density of about 1 transect per every
2 miles. An easy way to accomplish this is to put a large 2x2 mile grid across the landscape and use only
those points which fall into habitat as the sample. In all cases the grid should start at a random location.
Do not move the grid to get the highest number of points in habitat. One approach that may work well
is simply to use section boundaries as the grid. If these boundaries are not associated with vegetation
changes, then they can be thought of as random. If, however, there are specific features that are
generally associated with section boundaries, such as changes in forest age associated with
"checkerboard" ownership patterns in the West, then section boundaries will not work, and you will
need to start the grid at a random location.
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
