Alaskan Wildlife and Habitat Relations
Alaska
For my dissertation research, I assisted the Alaska Department of Fish and Game (ADFG) on their moose calf mortality study. Over the past 10 years, the moose population in McGrath, Alaska has been below the level required to meet subsistence needs of locals. As a result, ADFG undertook an investigation as to determine the fate of their moose calves. Fish and Game radio-collared 50 adult and sub-adult cow moose and monitored their movement and reproductive status from 2001-2003. All calves born to the cows were captured, radio-collared and monitored for subsequent survival throughout the summer months. We investigated all calf mortality-sites on a daily basis and their ultimate cause of death was resolved from scat, hair and carcass disposition. Simultaneously while at the moose calf mortality sites, I investigated understory and overstory vegetation characteristics with the intent of capturing predator preference in hunting habitats.
Based on summer 2001-2002 moose calf mortality results, ADFG determined that calf recruitment was limited by bear predation during parturition season. Adding a predator dimension to the study in 2002, twenty GPS-collars were deployed on black bears to monitor their habitat use in reference to moose calving grounds as they exit dens in April. Black bear females maintained smaller home ranges throughout the year as compared to males. Additionally, mixed and coniferous forests were selected more than other habitats for den sites.
There were four major areas of investigation in my Ph.D. thesis:
1) Spatio-temporal patterns of predation by multiple predators on a single species of prey
2) Black bear movements and habitat use during moose parturition
3) Black bear den-site characteristics in southwestern interior Alaska
4) Timing and synchrony of moose parturition in relation to predation risk
Our findings also suggest that male black bears overlap with other GPS-collared competing black bears and conspecific black bear during the peak period of predation on moose calves. This finding may be a function of over-abundance of moose calves in the area, resulting in potential predator satiation.
For my dissertation research, I assisted the Alaska Department of Fish and Game (ADFG) on their moose calf mortality study. Over the past 10 years, the moose population in McGrath, Alaska has been below the level required to meet subsistence needs of locals. As a result, ADFG undertook an investigation as to determine the fate of their moose calves. Fish and Game radio-collared 50 adult and sub-adult cow moose and monitored their movement and reproductive status from 2001-2003. All calves born to the cows were captured, radio-collared and monitored for subsequent survival throughout the summer months. We investigated all calf mortality-sites on a daily basis and their ultimate cause of death was resolved from scat, hair and carcass disposition. Simultaneously while at the moose calf mortality sites, I investigated understory and overstory vegetation characteristics with the intent of capturing predator preference in hunting habitats.
Based on summer 2001-2002 moose calf mortality results, ADFG determined that calf recruitment was limited by bear predation during parturition season. Adding a predator dimension to the study in 2002, twenty GPS-collars were deployed on black bears to monitor their habitat use in reference to moose calving grounds as they exit dens in April. Black bear females maintained smaller home ranges throughout the year as compared to males. Additionally, mixed and coniferous forests were selected more than other habitats for den sites.
There were four major areas of investigation in my Ph.D. thesis:
1) Spatio-temporal patterns of predation by multiple predators on a single species of prey
2) Black bear movements and habitat use during moose parturition
3) Black bear den-site characteristics in southwestern interior Alaska
4) Timing and synchrony of moose parturition in relation to predation risk
Our findings also suggest that male black bears overlap with other GPS-collared competing black bears and conspecific black bear during the peak period of predation on moose calves. This finding may be a function of over-abundance of moose calves in the area, resulting in potential predator satiation.
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