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North Pacific Research Board Project Final Report NORTH PACIFIC RESEARCH BOARD PROJECT FINAL REPORT Synthesis of Marine Biology and Oceanography of Southeast Alaska NPRB Project 406 Final Report Ginny L. Eckert1, Tom Weingartner2, Lisa Eisner3, Jan Straley4, Gordon Kruse5, and John Piatt6 1 Biology Program, University of Alaska Southeast, and School of Fisheries and Ocean Sciences, University of Alaska Fairbanks, 11120 Glacier Hwy., Juneau, AK 99801, (907) 796-6450, [email protected] 2 Institute of Marine Science, University of Alaska Fairbanks, P.O. Box 757220, Fairbanks, AK 99775-7220, (907) 474-7993, [email protected] 3 Auke Bay Lab, National Oceanic and Atmospheric Administration, 17109 Pt. Lena Loop Rd., Juneau, AK 99801, (907) 789-6602, [email protected] 4 University of Alaska Southeast, 1332 Seward Ave., Sitka, AK 99835, (907) 774-7779, [email protected] 5 School of Fisheries and Ocean Sciences, University of Alaska Fairbanks, 11120 Glacier Hwy., Juneau, AK 99801, (907) 796-2052, [email protected] 6 Alaska Science Center, US Geological Survey, Anchorage, AK, 360-774-0516, [email protected] August 2007 ABSTRACT This project directly responds to NPRB specific project needs, “Bring Southeast Alaska scientific background up to the status of other Alaskan waters by completing a synthesis of biological and oceanographic information”. This project successfully convened a workshop on March 30-31, 2005 at the University of Alaska Southeast to bring together representatives from different marine science disciplines and organizations to synthesize information on the marine biology and oceanography of Southeast Alaska. Thirty-eight individuals participated, including representatives of the University of Alaska and state and national agencies. A workshop report was submitted to NPRB in August, 2005 that details the results of this successful workshop. One of the goals of the workshop was to synthesize research on Southeast Alaska for publication in peer-reviewed journals. Twenty-one titles were proposed in response to an open call for papers, and seven were submitted to the Journal of Biogeography in Fall 2006. Papers are currently in revision for publication. KEYWORDS Southeast Alaska, marine biology, oceanography, fish, marine mammals, seabirds, intertidal, fisheries CITATION Eckert, G.L., T. Weingartner, L. Eisner, J. Straley, G. Kruse, and J. Piatt. 2007. Synthesis of marine biology and oceanography of Southeast Alaska. North Pacific Research Board Final Report 406, 78 p. 2 TABLE OF CONTENTS ABSTRACT .................................................................................................................................................................2 TABLE OF CONTENTS ............................................................................................................................................3 STUDY CHRONOLOGY...........................................................................................................................................5 INTRODUCTION .......................................................................................................................................................5 OVERALL OBJECTIVES .........................................................................................................................................5 CHAPTER 1 WORKSHOP REPORT ......................................................................................................................6 EXECUTIVE SUMMARY.......................................................................................................................................8 WORKSHOP SYNOPSIS ......................................................................................................................................10 Introduction........................................................................................................................................................10 Oceanography Overview....................................................................................................................................10 Physical Oceanography – Southeast Alaska ......................................................................................................10 Physical Oceanography – Gulf of Alaska ..........................................................................................................12 Biological Oceanography...................................................................................................................................13 Oceanography General Discussion ...................................................................................................................18 Fisheries Overview ............................................................................................................................................19 Fisheries General Discussion ............................................................................................................................23 Nearshore Ecology Overview ............................................................................................................................25 Nearshore Ecology General Discussion ............................................................................................................27 Seabirds Overview .............................................................................................................................................29 Seabirds General Discussion .............................................................................................................................33 Marine Mammals Overview...............................................................................................................................35 Marine Mammals General Discussion...............................................................................................................37 WORKSHOP FINDINGS AND RECOMMENDATIONS ..................................................................................39 Appendix 1. Workshop Agenda ............................................................................................................................42 Appendix 2. List of Attendees ...............................................................................................................................44 CHAPTER 2. SOUTHEAST ALASKA: OCEANOGRAPHIC HABITATS AND LINKAGES .......................48 INTRODUCTION........................................................................................................................................................48 Figure 1. Map of Southeast Alaska showing major channels (italicized), land masses (plain text) and cities (red)....................................................................................................................................................................50 GEOLOGICAL SETTING ............................................................................................................................................50 METEOROLOGICAL SETTING ...................................................................................................................................51 Figure 2. Mean monthly alongshore wind velocity over the Southeast Alaska continental shelf in 2003. The means were computed from the National Data Buoy Center (NDBC) meteorological buoy at Fairweather Grounds (58.24N, 134.28W) and the Environment Canada buoy at West Dixon Entrance (54.16N, 134.28W). The principal axis is the projection of the wind vector in the local alongshore direction. .................................52 Figure 3. A barrier jet along the outer shelf of Southeast Alaska, Dec. 30, 2000 (left) and gap winds within and emanating from channels in Southeast Alaska, Jan. 29, 2004 (right). Figures are courtesy of N. Winstead and additional examples are found at: http://fermi.jhuapl.edu/people/winstead/web_wind/index.html). ..........53 Figure 4. A circulation schematic for the Gulf of Alaska including the basin current structure (N. Pacific Current, Alaska Current and Alaskan Stream) and the Alaska Coastal Current on the continental shelf. The vertical bars indicate the annual precipitation rate compiled from historical coastal precipitation measurements. Data for the central Gulf of Alaska are from Baumgartner and Reidel, 1975...........................54 Figure 5. Mean monthly coastal freshwater discharge into the Gulf of Alaska (after Royer, 1982]. ...............54 3 OCEANOGRAPHIC SETTING .....................................................................................................................................55 Figure 6. Mean annual dynamic topography in 2002 (top) and 2005 (bottom) for the Gulf of Alaska inferred from autonomous profiling floats. The transport parallels the contours with clockwise (counterclockwise) flow around centers of low (high) dynamic topography as suggested by the red arrows. (Courtesy Project ARGO and H. Freeland: http://www.pac.dfo-mpo.gc.ca/sci/osap/projects/argo . Additional details are found in Freeland and Cummins, 2005].......................................................................................................................56 Figure 7. Sea Surface Height Anomaly (SSHA) map of the Northeast Gulf of Alaska on Feb. 23, 2003. Positive anomalies are eddies in which the interior flow is clockwise around the eddy center and negative anomalies imply counter-clockwise motion about the eddy center. The figure shows three prominent eddies (one counterclockwise eddy
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