Couch potatoes do better: Delayed dispersal and territory size affect the duration of territory occupancy in a monogamous mammal. Issue 12 (10th May 2017)

• Record Type: Journal Article
• Authors: Mayer, Martin; Zedrosser, Andreas; Rosell, Frank
• Is Part Of: Ecology and evolution. Volume 7:Issue 12(2017:Jul.)
• Page Start: 4347
• Page End: 4356
• Publication Date: 2017-05-10
• Subjects: Castor fiber -- dispersal -- Eurasian beaver -- fitness -- life history -- territoriality; Ecology -- Periodicals; Evolution -- Periodicals; 577.05
• DOI: 10.1002/ece3.2988
• Languages: English
• ISSNs: 2045-7758

Abstract

Abstract: In territorial, socially monogamous species, the establishment and defense of a territory are an important strategy to maximize individual fitness, but the factors responsible for the duration of territory occupancy are rarely studied, especially in long‐lived mammals. A long‐term monitoring program in southeast Norway spanning over 18 years allowed us to follow the individual life histories of Eurasian beavers ( Castor fiber ) from adolescence in their natal family group to dispersal and territory establishment until the end of territory occupancy. We investigated whether territory size, resource availability, population density, and dispersal age could explain the duration of territory occupancy, which ranged from 1 to 11 years. The duration of territory occupancy was positively related to dispersal age, suggesting that individuals that delayed dispersal had a competitive advantage due to a larger body mass. This is in support with the maturation hypothesis, which states that an animal should await its physical and behavioral maturation before the acquisition of a territory. Further, we found that individuals that established in medium‐sized territories occupied them longer as compared to individuals in small or large territories. This suggests that large territories are more costly to defend due to an increased patrolling effort, and small territories might not have sufficient resources. The lifetime reproductive success ranged from zero to six kits and generally increased with an increasing duration of territory occupancy. Our findings show the importance of holding a territory and demonstrate that dispersal decisions and territory selection have important consequences for the fitness of an individual. Abstract : We followed individual life histories of Eurasian beavers in southeast Norway over 18 years to investigate the factors affecting the duration of territory occupancy. Individuals that delayed dispersal and established in medium‐sized territories occupied their territory longer than normal dispersers and individuals in smaller or larger territories. Generally, there was a positive relationship between the duration of territory occupancy and lifetime reproductive success, demonstrating the importance of retaining a territory to increase fitness.