Download citation...
Question
Asked 25 May 2014

Is it possible to estimate population density from line transect encounter data with no distance metric, simply frequency of encounter data?

I have several years of encounter data for spoor on a network of transects in an isolated National Park. The data do not include a distance metric (therefore the programme Distance doesn't work), but are simply record the frequency and location of encounters along a network of transects. The study species has a home range of approximately 1km2, is it possible to estimate population density from these data? Thank you!
Fernando Arce
Mississippi State University
Also, Thinking a bit, you can use occupancy modelling but still you will have to split the transect in several sub-units but still need to define thewith of the belt. If your tapir is rare or have low density or detectability it could perform. Search for some papers about tigers and some references about using occupancy as a surrogate for rare or elusive species. You can get some feedback about it suitability for your project in: https://www.researchgate.net/publication/26410981_Occupancy_as_a_surrogate_for_abundance_estimation
Or in:
Conn, P. B., L. L. Bailey, and J. R. Sauer. 2004. Indexes as surrogates to abundance for low abundance species. Pages 59–74 in W. L. Thompson, editor. Sampling rare and elusive species: concepts, designs, and techniques for estimating population parameters. Island Press, Washington, D.C., USA