A Radiotracking Study of Home Range and Activity of the Brown Lemming (Lemmus trimucronatus)

Abstract

Home range was determined for brown lemmings by a radiotracking procedure throughout June and July 1972–1973 with 1795 location fixes obtained for 12 adult males, 10 adult females, and three juveniles (<20 grams) in 1972 and 3000 fixes recorded from 13 males and 12 females in 1973. Home range was calculated by the minimum area method. For 1972 animals mean male home range measured 1.33 ha (hectare) (S.D. .986, range .183 to 2.85 ha); mean female home range was .681 ha (S.D. .901, range .143 to 1.454 ha). For 1973 animals, mean male home range was .876 ha, (S.D. 1.0, range .0004 to 2.80 ha); mean female home range was .413 ha, (S.D. 1.03, range .015 to 1.68 ha). Males tended to have larger home ranges than females; 1972 home ranges tended to be larger than those of 1973 but these differences were not statistically significant. An indirect measure of activity termed change in location was defined as a difference of 2° or more in successive fixes. An analysis of this measure indicated males were significantly more active than females during both years, and 1972 animals were significantly more active than those studied in 1973. Activity was also measured directly by a telemetering system. For a sample of three males and three females, it was determined that males were active (for example, moving, feeding, and grooming) 75 percent of the time during a 24-hour period; females were active 67 percent of the time. Males spent about 69 percent of a 24-hour period outside of burrows, females 55 percent.