Evaluating elk habitat interactions with GPS collars

Abstract

Global positioning systems (GPS) are likely to revolutionize animal telemetry studies. GPS collars allow biologists to collect systematically scheduled data when VHF telemetry data is difficult or impossible to collect. Past studies have shown that the success of GPS telemetry is greater when animals are standing, or in open habitats. To make effective use of GPS telemetry, biologists need to understand its advantages and disadvantages. Our objectives are to compare data from GPS and VHF telemetry, present data on the use of activity sensors for estimating behavior and show that unsuccessful GPS fix attempts can provide insights into the biology of elk. We placed two GPS telemetry collars, capable of remote transmission of data to a command unit, and 44 VHF telemetry collars on adult female (cow) elk (Cervus elaphus).The GPS collars were programmed to take three fixes, three days each week. These GPS collars did not operate properly. In February 2000, we placed four store-on-board GPS collars from a different manufacturer on cow elk. These collars were programmed to collect 6 - 12 locations each day, with drop-off mechanisms set for December 1, 2000. The average success in acquiring fixes was 88%, with 70 % 3D locations. Each GPS collar collected more locations of elk than were obtained by three technicians working >2 yr using VHF telemetry. Tiltswitch activity sensors suggested that elk were feeding in 40% of locations. The data indicated that feeding and bedding occurred in all habitats. As expected, elk appeared to spend more time feeding than bedded in grasslands during both daytime and night-time hours. Disparity between the number of feeding and bedding locations in grasslands was less during night-time. Unsuccessful GPS fix attempts occurred more often when elk were bedded (P < 0.0 1) and more often during daytime than night-time or the crepuscular periods (P

Citation

Rumble, Mark A.; Benkobi, Lakhdar; Lindzey, Fredrick; Gamo, R. Scott. 2001. Evaluating elk habitat interactions with GPS collars. Tracking animals with GPS: an international conference held at the Macaulay Land Use Research Institute, Aberdeen, 12-13 March 2001. Aberdeen, UK: Macaulay Institute, 2001. p. 11-17