"Bowhead Whale 'SNACS' Near Barrow, Alaska: a Study of Environmental & Anthropogenic Variability"
Presenter: Sue Moore, AFSC, currently stationed at APL-UW.
When: Tuesday, March 20, 2007, 11:00am
Where: Traynor Seminar Rm (2076), Bldg. 4, AFSC, Sand Point Campus, Seattle, Washington
- This seminar will be transmitted live to the Auke Bay Laboratory (main conference room), and to the Newport Laboratory (BFB - Room 201).
- When arriving from off the WRC campus, leave extra time to check in with security at the gate and at the entrance to building 4.
Abstract:
The annual migration of bowhead whales (Balaena mysticetus) past Barrow, Alaska has provided subsistence hunting opportunities to Native whalers for centuries. Hunting in autumn is often facilitated by bowheads that linger to feed near Barrow, presumably on recurrent aggregations of their zooplankton prey (e.g., copepods, euphausiids). The bio-physical mechanisms that underlie this localized prey availability, which slows the whales and (thereby) assists the hunters, are poorly known. In 2004, a multi-disciplinary scientific team competed successfully for funding to study this system, as part of the NSF/Study of Northern Alaska Coastal Systems (SNACS) program.
Oceanographic field-sampling and aerial surveys on the narrow continental shelf near Barrow and in Elson Lagoon were conducted during mid-August to mid-September of 2005 and 2006. Objective of the field sampling were to: (1) describe existing water mass types and plankton communities, (2) identify exchange of water and material between the shelf, lagoon and offshore, (3) identify biological and physical mechanisms of plankton aggregation, and (4) determine the distribution and behavior of bowhead whales. Provisional analyses of both years of data demonstrate the extent of inter-annual and shorter-term variability in the physical and biological conditions on the shelf was striking. Multiple water mass types were observed across the study region, with close coupling among water mass type, chemical (nutrient) characteristics and biological communities (e.g., plankton abundance and type). Short-term variability in hydrography was associated with changes in wind speed and direction that had a profound effect on the plankton taxonomic composition on the shelf. In particular, winds from the southwest along Barrow Canyon in early September 2006 apparently pushed Pacific Water, and euphausiids, onto the shelf near Barrow that subsequently were used by feeding bowhead whales. Sub-tidal fluxes of water in/out of Elson Lagoon likewise are tightly coupled to and co-vary with wind speed and direction; this mechanism may fill the lagoon with krill so that the lagoon system functions as a reservoir for krill.
Both of these mechanisms may contribute to the formation of a favorable feeding environment (i.e., SNACS) for the bowhead whale near Barrow. (The SNACS Sampling Team, listed alphabetically, is C. J. Ashjian, R. G. Campbell, J. C. George, S. R. Okkonen, B. F. Sherr, E. B. Sherr)
Presenter's Bio:
Sue Moore spent two years at the University of Michigan struggling along in the School of Journalism before realizing she did not want to be a journalist. Landing safely in sunny San Diego, she received BA in Biology from the University of California, San Diego (UCSD), focusing on the physiology of diving mammals. Soon after, she earned a MS in Biology from San Diego State University (SDSU), focusing on calling behavior of tree frogs (yep, tree frogs). Sue then took a 12-year hiatus from academia, spending much of her time flying surveys for whales offshore northern Alaska. Subsequently, she packaged up that decadal dataset as fodder for her doctorate at Scripps Institution of Oceanography, with a dissertation entitled “Cetacean Habitats in the Alaskan Arctic”, available on at least two library shelves since 1997. Sue has served as Director, and as Cetacean Program Leader, at the National Marine Mammal Laboratory (NMML) and is currently on detail to the Applied Physics Laboratory (APL) at the University of Washington (UW) to develop and support acoustic and Arctic-related research programs for the Alaska Fisheries Science Center.
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