13. Migration.ppt
- 1. Orientation, taxes, movements, and migration
- 2. phototaxis (light) geotaxis (gravity) chemotaxis - toward food, conspecifics, mates, offspring - away from predators, extract of human skin thigmotaxis - substrate – sculpins, gobies, anemone fish - conspecifics – sculpins rheotaxis (current) electrotaxis, galvanotaxis magnetotaxis – tuna? kineses - lamprey larvae Orientation and taxes
- 3. Migration "directed mass movements from one place to another on a regular basis"
- 4. Why migrate? (what are the benefits?) Where/when does it occur? What are the negative consequences of migration? So, why migrate anyway? Explain anadromy vs. catadromy
- 5. “(migration) occurs when the gain in fitness from using a second habitat minus the migration costs of moving between habitats exceeds the fitness from staying in only one habitat.” (Gross 1987)
- 6. Why migrate? Habitats for different life history periods vary But, there are liabilities: energetic costs drifting (getting lost, or displaced by currents) exposure to predation Migration
- 7. I. Function feeding (daily) follow food abundance breeding (seasonal) place offspring in their ideal habitat minimize potential for cannibalism wintering (seasonal) adjustment to temperature Migration may be horizontal OR vertical Migration
- 8. II. Timing daily (usually feeding) seasonal/annual (wintering and reproduction) lifetime - ontogenetic (e.g. salmon, lamprey) Migration adult feeding area nursery area spawning area
- 9. III. Environment diadromy: ocean fresh anadromy ocean fresh (to breed) catadromy fresh ocean (to breed) obligate (eel) facultative (sculpin) amphidromy fresh ocean or ocean fresh …but not for breeding (life cycle) potamodromy fresh fresh oceanodromy ocean ocean Migration
- 10. “The contrasting directions of migration can largely be explained by the relative availability of food resources in ocean and freshwater habitats." Gross et al. (1988) ___________________________________________________ relative level geographic predominating of productivity location migratory mode oceans > freshwaters temperate anadromy latitudes freshwaters > oceans tropical catadromy latitudes Migration
- 11. Partial migration vertical migration anadromous vs. landlocked species Migration
- 12. So…. How do we study migration? Open oceans are large….
- 14. Acoustic Telemetry Tags emit unique signal every 3 mins, for ~ 3 years
- 15. Acoustic Telemetry Receivers deployed singly, or in virtual positioning arrays
- 16. GLATOS – Great Lakes Acoustic Telemetry Observation System
- 20. 2012 – fish 29518 (wild male)
- 21. 2012 – fish 29497 (hatchery male)
- 22. Right Whale Listening Network (link)