Analysis of foraging movements of Atlantic bluefin tuna (Thunnus thynnus): individuals switch between two modes of search behaviour
Abstract
We investigate the application of quantitative techniques for distinguishing adaptive search behaviour in Atlantic bluefin tuna (Thunnus thynnus). The analysis demonstrates the application of a novel spectral analysis technique for resolving and measuring periodicity in animal behaviour patterns. Two different search strategies are identified that include regulation of turning (klinokinesis) and speed (orthokinesis). Our results provide evidence that bluefin tuna attempt to optimize their searching efficiency through adjustments in the duration and timing of switching between these two searching strategies. Repetitive, diurnal deep dives were also found to coincide with switching of search behaviour. Additional tracking experiments with larger sample sizes are needed to better identify how individuals switch between the two search strategies and how such decisions may collectively improve the searching and foraging efficiency of their schools (synchrokinesis, social taxis) in response to changes in the size or composition of prey aggregations.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Mar 10, 2004
- Source ID
- 10.1007/s10144-004-0169-9
Entities
People
- Molly E. Lutcavage
- Nathaniel K. Newlands
- Tony J. Pitcher
Organizations
- Natural Sciences and Engineering Research Council
- Office of Naval Research
- University of British Columbia
- University of New Hampshire