Moose Alces alces habitat use at multiple temporal scales in a human-altered landscape

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Habitat quality influences population distribution, individual space use and functional responses in habitat selection by a large herbivore

Identifying factors shaping variation in resource selection is central for our understanding of the behaviour and distribution of animals. We examined summer habitat selection and space use by 108 Global Positioning System (GPS)-collared moose in Norway in relation to sex, reproductive status, habitat quality, and availability. Moose selected habitat types based on a combination of forage quality and availability of suitable habitat types. Selection of protective cover was strongest for reproducing females, likely reflecting the need to protect young. Males showed strong selection for habitat types with high quality forage, possibly due to higher energy requirements. Selection for preferred habitat types providing food and cover was a positive function of their availability within home ranges (i.e. not proportional use) indicating functional response in habitat selection. This relationship was not found for unproductive habitat types. Moreover, home ranges with high cover of unproductive habitat types were larger, and smaller home ranges contained higher proportions of the most preferred habitat type. The distribution of moose within the study area was partly related to the distribution of different habitat types. Our study shows how distribution and availability of habitat types providing cover and high-quality food shape ungulate habitat selection and space use

On fitness and partial migration in a large herbivore – migratory moose have higher reproductive performance than residents

Partially migratory populations comprise both resident and migratory individuals. Th ese tactics may coexist if their demographic contribution to future generations (i.e. fitness) are equal or vary temporally with environmental conditions, or if individuals switch between being migrant and resident. Alternatively, the choice of movement tactic can be based on individual attributes such as age, competitive ability or personality. In the latter cases, the two tactics are not expected to have similar average fitness. In this study, we examined the eff ect of movement tactic on reproductive performance and survival of 82 GPS-marked female moose and their off spring in a partial migratory population in central Norway. The results indicated higher growth in the migrating part of the population because migrating females produced more twins than resident females. We found no diff erences in pregnancy rates or survival of adults or their off spring, indicating a net fitness benefit of being migrant. We found the average shoulder height of residents to be slightly lower than of migrants, but doubt that this aff ected their migration ability. A more likely explanation is that migratory females are both more fecund and grow bigger because of better conditions in their summer ranges. This may be a temporal phenomenon if the fitness differences between migratory and resident moose vary according to environmental fluctuations

Data - summersurvivalcalves

Data used to analyze summer survival of calves in relation to their mothers movement tactic

Data - shoulderheight and twinning

Data used to compare shoulderheight of resident and migrant female moose. And to test the effect of shoulderheight on the probabilty of having twins

Data - moose and altitude

Data used to examine if migrants and residents used different altitudes during the year

On fitness and partial migration in a large herbivore – migratory moose have higher reproductive performance than residents

Partially migratory populations comprise both resident and migratory individuals. Th ese tactics may coexist if their demographic contribution to future generations (i.e. fitness) are equal or vary temporally with environmental conditions, or if individuals switch between being migrant and resident. Alternatively, the choice of movement tactic can be based on individual attributes such as age, competitive ability or personality. In the latter cases, the two tactics are not expected to have similar average fitness. In this study, we examined the eff ect of movement tactic on reproductive performance and survival of 82 GPS-marked female moose and their off spring in a partial migratory population in central Norway. The results indicated higher growth in the migrating part of the population because migrating females produced more twins than resident females. We found no diff erences in pregnancy rates or survival of adults or their off spring, indicating a net fitness benefit of being migrant. We found the average shoulder height of residents to be slightly lower than of migrants, but doubt that this aff ected their migration ability. A more likely explanation is that migratory females are both more fecund and grow bigger because of better conditions in their summer ranges. This may be a temporal phenomenon if the fitness differences between migratory and resident moose vary according to environmental fluctuations

Data - totalcalfsurvival

Data used to analyze first year survival of calves in relation to their mothers movement tactic

Data from: On fitness and partial migration in a large herbivore – migratory moose have higher reproductive performance than residents

Partially migratory populations comprise both resident and migratory individuals. These tactics may coexist if their demographic contribution to future generations (i.e. fitness) are equal or vary temporally with environmental conditions, or if individuals switch between being migrant and resident. Alternatively, the choice of movement tactic can be based on individual attributes such as age, competitive ability or personality. In the latter cases, the two tactics are not expected to have similar average fitness. In this study, we examined the effect of movement tactic on reproductive performance and survival of 82 GPS-marked female moose and their offspring in a partial migratory population in central Norway. The results indicated higher growth in the migrating part of the population because migrating females produced more twins than resident females. We found no differences in pregnancy rates or survival of adults or their offspring, indicating a net fitness benefit of being migrant. We found the average shoulder height of residents to be slightly lower than of migrants, but doubt that this affected their migration ability. A more likely explanation is that migratory females are both more fecund and grow bigger because of better conditions in their summer ranges. This may be a temporal phenomenon if the fitness differences between migratory and resident moose vary according to environmental fluctuations