Striped bass scales and life history tales: Elizabeth North UMCES Horn Point Laboratory fish and physics in Chesapeake Bay Striped bass scalesEggs Size: 1.8 3.7 mm Duration: 2 days Distance: 10 km Adults Size: m Duration: 35 years Distance: 1000 kmNote: Source for images is listed the first time the image is used. Life history tales Fish photographs by D. Flescher, downloaded fromFish illustrations from: Lippson, A. J. and R. L. Moran Manual for identification of early developmental stages of fishes of the Potomac River Estuary. Prepared for MD DNR Power Plant Siting Program. PPSP-MP pp. LarvaeJuveniles Adults Eggs Physical conditions affect all life stages Water temperature, salinity, dissolved oxygen concentrations, and currents influence: survival (heat shock, winter mortality) growth rates location, movement, migration Striped bass distribution Chesapeake Bay To understand how physical conditions affect striped bass in Chesapeake Bay, we need to: determine how physical conditions change in Chesapeake Bay identify how striped bass respond to physical conditions Outline 1.Water temperature 2.Dissolved oxygen Water TemperatureChesapeake Bay Program Monitoring Data (Click on plot to see animation) Striped bass and water temperature: lethal limits and optimal ranges Juveniles Adults Stress/Mortality Optimal oCoC oCoC Stress/Mortality Setzler-Hamilton and Hall 1991 Winter: deep water is best habitat Late summer: often deep water is preferable Last month: surface waters warming up (This plot should be updated before giving the presentation) This week: rockin Chesapeake Bay Observing System(This plot should be updated before giving the presentation) Outline 1.Water temperature 2.Dissolved oxygen Dissolved Oxygen Chesapeake Bay Program Monitoring Data (Click on plot to see animation) Physics and biology cause low dissolved oxygen Fall overturn: low stratification, high mixing Spring rainfall: high stratification, low mixing Physics and biology cause low dissolved oxygen High stratification, low mixing + Warm water temperatures + Crankin biology Phytoplankton Bacteria = Low dissolved oxygen Striped bass and dissolved oxygen concentrations: lethal limits JuvenilesAdults Stress Mortality Preferred Setzler-Hamilton and Hall 1991 Winter: all is good Late summer: deep water is NOT preferable Last month: deep water is poor habitat (This plot should be updated before giving the presentation) Water temperature Dissolved Oxygen Habitat squeeze: high temperatures and low dissolved oxygen August 18-20, 2003 Summary Physical conditions affect all life stages of striped bass Understanding changes to striped bass habitat is important for fisheries management Habitat quality is determined by a suite of physical conditions Acknowledgements Edward Houde, William Boicourt University of Maryland Center for Environmental Science Literature Cited Setzler-Hamilton, E. M., and L. Hall Jr (1991) Striped bass, Morone saxatilis. In: Funderburk SL, Jordan SJ, Mihursky JA, Riley D (eds) Habitat Requirements for Chesapeake Bay Living Resources. Chesapeake Bay Program, Annapolis, Maryland, p National Science Foundation UMCES A web-based classroom activity Where could the stripers be? based on this talk can be found at: Regards, Elizabeth W. North Assistant Professor University of Maryland Center for Environmental Science Horn Point Laboratory, P. O. Box 775 Cambridge, MD USA Note to Teachers: If you use this presentation or web-based activity in your classroom, would you please send me an? Id like to know if my efforts are applied in the classroom. Also, I would certainly appreciate your comments and suggestions on making the presentation or web-based activity more useful to you.