A Method for Distinguishing Dispersal from Death in Mark-Recapture Studies

Publisher Website
Google Scholar
Abstract
We present a method for estimating the distribution of dispersal distances and using it to obtain an accurate measure of the population death rate in mark-recapture studies. The actual distances between successive captures of the same individuals are used to calculate the expected frequency with which individuals move different distances, correcting for the proportion of area at each distance that is actually sampled by traps. We can then calculate the expected rate at which individuals have moved off the grid, and by subtracting this number from the rate of disappearance of marked individuals we obtain an accurate estimate of death rate. We illustrate the method by calculating the death rate for a population of Dipodomys merriami in the Chihuahuan Desert.