How many seabirds do we need to track to define home-range area?

摘要: 1. In recent years, marine predator and seabird tracking studies have become ever more popular. However, they are often conducted without first considering how many individuals should be tracked for long should in order to make reliable predictions of a population’s home-range area. 2. Home-range area analysis of two seabird-tracking data sets was used define the of active use (where birds spent 100% their time) core foraging birds spent 50% time). Analysis on trip undertaken by the birds then two, three four trips combined. Appropriate asymptotic models were applied data, calculated areas plotted as function of an increasing number individuals included sample. Data were extrapolated from these models predict active of the colonies sampled. 3. Significant variability found predictions made For shags, foraging trip predicted 56% smaller when compared by combining trips. kittiwakes, 43% predicted when comparing with combined trips. 4. The that would required home range the colony depends greatly analysis. This analysis predicted 39 (confidence interval 29–73) shags 83 (CI: 109–161) kittiwakes be required 95% are included sample 135 (CI 96–156) 248 (164–484) kittiwakes when only is analysis. 5. Synthesis applications. Seabird mammal increasingly being aid designation conservation zones important foraging areas. We suggest may underestimating size these foraging better estimates could both duration and number logger deployments. Researchers intending draw conclusions tracking data conduct similar this study determine the reliability predictions.