In my study, 161 individuals of _P. truei_ were caught from one to 13 times each. The estimated home ranges of 10 individuals of _P. truei_, each caught from eight to 13 times, were plotted and measured after each capture from the fourth to the last. The percentage of the total estimated range represented by the fourth through tenth captures was, respectively, 52, 65, 73, 85, 88, 93, and 96 per cent.

Ninety-seven individuals of _P. maniculatus_ were caught from one to 10 times each. For five individuals that were each caught from seven to 10 times, the percentage of total estimated range represented by the fourth through seventh captures was, respectively, 59, 69, 85, and 93 per cent.

Comparative Ecology of Pinyon Mice and Deer Mice in Mesa Verde National Park, Colorado — Part 19

The above percentages do not imply that the true home range of individuals of these species can be reliably estimated after seven or 10 captures; the average percentages do, however, indicate a fairly rapid increase in known size of home ranges between the fourth and tenth captures. The estimated home ranges of _P. maniculatus_ tended to reach maximum known size at about seven captures, whereas the estimated ranges of _P. truei_ tended to attain maximum known size after nine or more captures. The controversy over the number of captures of an individual animal required for a reliable estimate of its home range was not settled by my data.

Comparative Ecology of Pinyon Mice and Deer Mice in Mesa Verde National Park, Colorado — Part 19

I initially decided to estimate home ranges for animals caught five or more times and at three or more stations. Of the 282 animals caught and marked, only 48 were caught five or more times. Because of the small numbers of _P. maniculatus_ that were caught five or more times, I wanted to determine whether mice caught four times had an estimated range that was significantly smaller than that of mice caught five times. Eight individuals of _P. maniculatus_ were caught four times each, and it seemed desirable to use the data from these mice if such use was justified. Data from the 48 mice caught five or more times were used for this testing.

Comparative Ecology of Pinyon Mice and Deer Mice in Mesa Verde National Park, Colorado — Part 19

By means of a T-test, I compared the estimated ranges of those 48 mice following their fourth capture with ranges estimated after the fifth capture. The results did not demonstrate significant differences between the two sets of estimates; therefore, I decided to use data resulting from four or more captures, and at three or more stations.