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!

Ecology

Zoology

Wildlife Ecology

Wildlife Biology

Biodiversity Monitoring

Biodiversity Research

Fernando Arce

Mississippi State University

The only reasonable way that comes to my mind is to fix a width for detection (e.g. 100 m away form the transect line for both sides) and asume that detectability is perfect. Then , with that you get the area covered and the number of individuals detected and get an estimate (nº ind / area). It's not the best way but have been classically used in the past for estimating songbirds density (it is frecuently called "Finnish line-transect").

Still you can compare "densities" between transects or habitats in your study area whitout the need for explictly estimate density but detectability tipically varies between habitats so you must think about it carefully...