Striped bass scales

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Striped bass scales and life history tales
fish and physics in Chesapeake Bay
Elizabeth North UMCES Horn Point Laboratory
http//seawifs.gsfc.nasa.gov/SEAWIFS/
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Striped bass scales
Eggs Size 1.8 3.7 mm Duration 2
days Distance 10 km
Adults Size 0.5-2.0 m Duration 35
years Distance 1000 km
http//www.mdsg.umd.edu/MarineNotes/Sep-Oct98/
http//www.dnr.state.md.us/fisheries/education/roc
kfish/rockfish.html
Note Source for images is listed the first time
the image is used.
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Life history tales

Fish photographs by D. Flescher, downloaded from
www.fishbase.org
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Physical conditions affect all life stages
Water temperature, salinity, dissolved oxygen
concentrations, and currents influence
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Striped bass distribution
http//seawifs.gsfc.nasa.gov/SEAWIFS/
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Chesapeake Bay
http//seawifs.gsfc.nasa.gov/SEAWIFS/
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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
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Outline

• Water temperature
• Dissolved oxygen

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(Click on plot to see animation)
Water Temperature
Chesapeake Bay Program Monitoring Data
http//noaa.chesapeakebay.net/interpolatorimages/w
qbrowsersearch.aspx
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Striped bass and water temperature lethal
limits and optimal ranges
Adults
Juveniles
Stress/Mortality
Optimal
Optimal
Stress/Mortality
oC
oC
Setzler-Hamilton and Hall 1991
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Winter deep water is best habitat
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Late summer often deep water is preferable
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(This plot should be updated before giving the
presentation)
Last month surface waters warming up
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(This plot should be updated before giving the
presentation)
This week rockin
Chesapeake Bay Observing System http//www.cbos.or
g/download.php
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Outline

• Water temperature
• Dissolved oxygen

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(Click on plot to see animation)
Dissolved Oxygen
Chesapeake Bay Program Monitoring Data
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Physics and biology cause low dissolved oxygen
Fall overturn low stratification, high mixing
Spring rainfall high stratification, low mixing
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Physics and biology cause low dissolved oxygen
High stratification, low mixing
Warm water temperatures
Crankin biology
Bacteria
Low dissolved oxygen
Phytoplankton
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Striped bass and dissolved oxygen concentrations
lethal limits
Juveniles
Adults
Mortality
Stress
Preferred
Setzler-Hamilton and Hall 1991
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Winter all is good
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Late summer deep water is NOT preferable
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(This plot should be updated before giving the
presentation)
Last month deep water is poor habitat
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Habitat squeeze high temperatures and low
dissolved oxygen
August 18-20, 2003
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Summary
Physical conditions affect all life stages of
striped bass
Habitat quality is determined by a suite of
physical conditions
Understanding changes to striped bass habitat is
important for fisheries management
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Acknowledgements
Edward Houde, William Boicourt University of
Maryland Center for Environmental Science
National Science Foundation
UMCES
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.
13.1-13.31
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A web-based classroom activity Where could the
stripers be? based on this talk can be found at
http//northweb.hpl.umces.edu/education_outreach/e
ducation_outreach.htm
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Note to Teachers If you use this presentation
or web-based activity in your classroom, would
you please send me an e-mail? 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.
Regards,      Elizabeth W. North      Assistant
Professor      University of Maryland     Center
for Environmental Science     Horn Point
Laboratory, P. O. Box 775     Cambridge, MD
21613  USA      enorth_at_hpl.umces.edu