We assessed the spatial independence of fisher (Martes pennanti) detections at sooted aluminum track plates deployed in northwestern California during 1994 and 1995. We used six track plates with 1 km spacing to form a 5 km segment. We estimated the probability of detecting fishers using program CAPTURE. We evaluated temporal and spatial relations among track plates within each six-station segment using nonlinear regression and a randomization test. Estimated probabilities of initially detecting a fisher (capture) were 0.04 and 0.07, and probabilities of subsequent detection (recapture) were 0.36 and 0.3 in 1994 and 1995, respectively. A nonlinear regression of mean number of detections per segment on time had an upper asymptote of 1.22 indicating that detections at stations did not increase linearly through time. We found that on 25 of 30 segments, the observed data were likely to occur under the null hypothesis of no dependency. The segments with potential spatial dependencies were characterized by low numbers of detections (≤4 out of a possible 66) and did not effect conclusions. We viewed the results of the randomization test and the regression as evidence that fisher detections at track plates were not dependent upon previous detections at neighboring track plates. However, because individual fishers were not marked, we could not assess independence with respect to individual animals. When using between-station distances similar to those evaluated in this study, individual track plates are appropriate sampling units for indexing populations, assessing trends or for future investigations of habitat use.