Predation Control Efforts Underway Near McGrath
Efforts by Division of Wildlife Conservation staff, in coordination with local residents, to alleviate predation on moose calves in Game Management Unit 19D near McGrath, are in progress.
In March, Division of Wildlife Conservation staff initiated efforts to help private trappers locate carcasses of wolf-killed moose in and near the 520 square mile Experimental Micro Management Area (EMMA) surrounding McGrath. Placing traps around carcasses of wolf-killed moose is a widely-recognized method of increasing trapping success for wolves. About 8-10 local pilots and trappers have been consistently seeking wolves all winter whenever snow conditions were suitable. Poor snow conditions prevailed for much of the winter, but conditions were perfect during the last week of March and the first week of April. During this two-week period, Department staff conducted nine airplane and helicopter flights and shared information about wolf pack movements and moose kill sites with the trappers. While no wolves were authorized to be taken by helicopter, to date 13 wolves have been harvested compared to the average annual harvest of 12. Wolf trapping and hunting seasons in this area close on April 30.
Starting in mid-May through early June, Division of Wildlife Conservation staff will remove bears from the EMMA in an attempt to increase the number of moose calves that survive to November. Biologists, a staff wildlife veterinarian, and contractors will ground-trap or dart bears from helicopters then fly them in fixed-wing aircraft to remote state lands at least 150 miles from McGrath. About 20 bears will be radiocollared to determine when or if they return to the EMMA. Up to about 50 bears will be moved, but sows with first-year cubs will not be moved.
Also, for the third consecutive year, a moose calf mortality study will be conducted this spring during the same time period as the bear removal. About fifty newborn moose calves will be fitted with special radiocollars that emit a “mortality” signal if the calf dies. The collars will allow biologists to determine the location and time of death. Biologists will monitor the survival of the collared moose calves until they are at least a year old. By observing the collared calves, and also by determining the proportion of moose calves among the population counted during fall aerial surveys, biologists will be able to determine if removing bears can significantly increase the survival of moose calves.
The Board of Game reviewed the most recent biological data on wolves and bears and harvest data on moose in the McGrath area at its March meeting, and endorsed efforts to reduce predation on moose, especially moose calves. Results of calf mortality studies in 2001 and 2002 indicated that wolves, black bears, and grizzly bears kill about 60-70% of all moose calves from birth to one year of age. Wolves and black bears each killed about 25-30% of the calves. Almost all bear predation, primarily on calves, occurred during May-July. Wolf predation on calves and other ages of moose occurred year round.