Jul 21, 2015

Using GPS collars to determine parturition and cause-specific mortality of moose calves

Severud, William J., Giudice, Glenn Del, Obermoller, Tyler R., Enright, Thomas A., Wright, Robert G., Forester, James D.
Wildlife Society Bulletin
  • States need for information on neonatal survival and cause-specific mortality of moose neonates
  • Researchers monitored hourly movements of GPS-collared females for indications of calving
  • From May 2 to June 2, 2013, researchers observed 47 of 73 collared females (50 known pregnant, 17 not pregnant, 6 unknown pregnancy status) make “calving movements” followed by a clustering of locations
  • Researchers approached calving sites (after allowing a mean bonding time of 40.2 hr) and captured and GPS-collared 49 neonates from 31 dams
  • Researchers closely monitored dam–calf movements and launched rapid investigative responses to calf mortality notifications to determine cause of mortality
  • Twenty-five of 34 calves (74%) died of natural causes as of 31 December 2013, including 1 after natural abandonment, 1 after abandonment of unknown cause, 1 drowning, 1 unknown predator kill, 1 lethal infection from wolf (Canis lupus) bites, 4 black bear (Ursus americanus) kills, 12 wolf kills, and 4 “probable wolf kills"
  • Research has implications for moose population management