INTERPRETING BEHAVIOR FROM ACTIVITY COUNTERS IN GPS COLLARS OF MOOSE

Abstract

Activity patterns of free-ranging moose can be estimated from activity counts on radiotelemetry collars. We observed a collared moose to calibrate activity counts on a collar to activities of moose in natural habitats. If activity counts on the collar were low, it was likely that the moose was inactive. However, we recorded high activity counts when the moose was active and on 25% of time intervals when the moose was inactive. The high activity counts were probably due to collar placement and possibly due to bugs in the software of the prototype colour we used in 1994. We also analyzed activity counts from collars on 6 free-ranging moose which were not directly observed in 1995. Activity counts were lower from collars on free-ranging moose than from direct observations because collars were placed higher and tighter on the neck. There were cyclic periods of activity and inactivity throughout a 24-hour period when activity counts were taken every 10 minutes on free-ranging moose. We averaged activity counts on 10-minute interrvals to simulate GPS observation intervals of 1 to 4 hours typically used in this GPS collar. The correspondence between averaged activity counts and percent of time spent active each day decreased if activity counts were averaged over 2 hr because feeding and bedding periods occur together within the averaging period. We caution that this could affect interpretation of daily activity patterns of moose activity counts averaged over periods longer than 1 hour.