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Marine Science in Alaska: 2007 Symposium Book of Abstracts

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Marine Science in Alaska: 2007 Symposium Book of Abstracts Sponsoring Organizations Alaska Department of Fish and Game Alaska Fisheries Science Center Alaska Ocean Observing System Alaska Pacific University Alaska Sea Grant Alaska SeaLife Center Exxon Valdez Oil Spill Trustee Council Kachemak Bay Research Reserve Minerals Management Service National Ocean Service North Pacific Fishery Management Council North Pacific Research Board Oil Spill Recovery Institute Pollock Conservation Cooperative Research Center Prince William Sound Science Center University of Alaska Fairbanks US Arctic Research Commission USGS Alaska Science Center Marine Science in Alaska: 2007 Symposium Book of Abstracts ! Sunday, 20 January: Welcome • Evening: Poster Reception ! Monday, 21 January: Bering Sea and Aleutian Islands • Welcome • Keynote Address: Jonathan Heifetz Deep Sea Coral Distribution and Habitat in the Aleutian Archipelago • Morning: Climate, Oceanography, Ecosystem Perspectives, Lower Trophic Levels & Fish • Lunch: Michelle Ridgeway • Afternoon: Fish and Fish Habitat, Seabirds, Marine Mammals & Humans • Evening: Poster Reception & Student Presentations ! Tuesday, 22 January: Gulf of Alaska • Morning: Climate and Oceanography, Ecosystem Perspectives, Lower Trophic Levels & Fish and Fish Habitat • Lunch • Afternoon: Fish and Fish Habitat, Seabirds, Marine Mammals & Community Involvement • Evening: Poster Reception & Beluga Whale Panel Discussion ! Wednesday, 23 January Gulf of Alaska (continued) • Morning 1: Marine Mammals ! Arctic • Morning 2: Climate and Oceanography • Lunch • Afternoon: Ecosystem Perspectives, Fish and Fish Habitat, Seabirds, Marine Mammals & Humans Keynote: Bering Sea & Aleutian Islands Deep Sea Coral Distribution and Habitat in the Aleutian Archipelago Jonathan Heifetz, [email protected], NOAA Fisheries, AFSC, Auke Bay Laboratories, Ted Stevens Marine Research Institute Douglas Woodby, [email protected], Alaska Department of Fish and Game Jennifer R. Reynolds, [email protected], School of Fisheries & Ocean Sciences, University of Alaska Fairbanks Robert P. Stone, [email protected], NOAA Fisheries, AFSC, Auke Bay Laboratories A unique feature of the benthic environment of the Aleutian Archipelago is a highly diverse and abundant coral and sponge community. Coral abundance far exceeds that reported for other high latitude areas of the world and there are many endemic species. Habitat mapping of seventeen sites covering 2,600 km2 at depths of 30 – 3,800 m coupled with visual observations to 2,950 m were used to collect biological information and develop predictive models that relate coral and sponge distribution to environmental characteristics. Habitats dominated by bedrock and cobble supported the highest densities of corals. Diversity of corals and sponges increased from deep to shallow water. For the predictive model, explanatory variables included depth, slope, and rugosity with depth and slope being the most important factors. Models of coral and sponge presence/absence north of the Aleutian Islands Archipelago were more successful than models south of the Archipelago. The most damage and disturbance to coral and sponge communities occurred at depths < 800 m which generally corresponded to the depth limit of the majority of fisheries that use bottom contact gear. There was a consistent positive relationship between damage and disturbance levels and intensity of bottom trawling, whereas results varied for other gear types. Some commercial fish and crab species aggregate in habitats where corals are abundant, making these habitats at risk to fishing gear impacts. Protective measures implemented in the Aleutian Islands include restricting bottom trawling to historically fished areas. While this protective measure may halt the expansion of bottom trawling to areas not fished, the conservation of coral and sponge habitat in fished areas is still of primary concern. Bering Sea & Aleutian Islands Climate, Oceanography, Ecosystem Perspectives, Lower Trophic Levels & Fish Monday, 21 January 2008 9:30 AM – 12:15 PM Session Chair: Francis Wiese North Pacific Research Board TALKS Speaker Title SE Bering Sea Shelf: A Contrast Between a Warm Year (2005) and a Phyllis J.Stabeno Cool Year (2007) Carol Ladd North Pacific Meets the Bering Sea: Transport Through Amukta Pass Macroecological Patterns in North Pacific Ecosystem Dynamics: Spatio- Bill J. Sydeman Temporal Co-Variation in Upper and Lower Trophic Level Diversity and Productivity From Canada to Japan Georgina A. An Ecosystem model for the SE Bering Sea with Benthic Infauna Gibson Stephen Jewett Retrospective Analyses of Norton Sound, Alaska Benthic Fauna Tracie Erin A Temporal Comparison of Benthic Community Structure SW of St. Merrill* Lawrence Island Community Structure of Eastern Bering Sea Epibenthic Invertebrates Cynthia Yeung from Annual Summer Bottom Trawl Surveys, 1982-2002 Jacqueline Biological Community Response to Changing Sea Ice and Hydrographic Grebmeier Conditions in the Northern Bering Sea Ecosystem Projections of Kuskokwim River Chum Salmon Runs Based on IPCC Nicholas A. Bond Model Simulations Temperature Effects on Larval Snow Crab Transport and Source-Sink Sarah Hinckley Relationships in the Bering Sea: How Will Larval Settlement Success be Affected by Climate Change? * Student Presentation Bering Sea & Aleutian Islands - Climate and Oceanography SE Bering Sea Shelf: A Contrast between a Warm Year (2005) and a Cool Year (2007) Phyllis J. Stabeno, [email protected], NOAA Pacific Marine Environmental Lab Calvin W. Mordy, [email protected], University of Washington Jeffrey M. Napp, [email protected], NOAA Fisheries, Alaska Fisheries Science Center The recent warm period (2001-2005) in the Bering Sea culminated in 2005 when maximum ice extent did not extend over much of the southern shelf and depth averaged water temperatures in late summer were ~8°C. Since then there has been a transition to cooler conditions, with ice extent and ocean temperatures in 2007 comparable to the cooler conditions observed in the late 1980s and early 1990s. In May and again in September/October 2005, hydrographic surveys were completed along the 70-m isobath from north of the Alaska Peninsula to almost St. Lawrence Island. In 2007, most of the same stations were occupied in April (as part of NSF’s Bering Sea Ecosystem Study) and again in September/October. Temperature, salinity, nutrients, fluorescence, chlorophyll and oxygen were measured at each of ~55 hydrographic stations. Zooplankton were sampled at selected stations. Many of the ocean properties varied as expected: in 2007 temperatures were 1-3°C cooler than in 2005 with a cold pool persisting during entire summer; and the ocean was less saline than in 2007 than in 2005. Some of the observations, however, were not expected. In late summer 2005, there was a sharp transition between the southern (warm, saline) shelf and the northern (cooler, less saline) shelf. In 2007, the transition was less distinct, but it formed in a similar location to the south of St. Matthew Island, despite the much more extensive and persistent ice cover in 2007. Intrusions of higher salinity water occurred between St. George Island and St. Matthew Islands during both years. Nutrient levels also differed between the two years, with the high ammonium and nitrite concentrations observed in 2005 absent in 2007. The fall phytoplankton bloom appears to be more extensive in 2007 than in 2005. Differences in the zooplankton population will also be discussed. Understanding the differences between these two years and the mechanisms that control the lower trophic level dynamics, will help us forecast how the Bering Sea will respond during the next decades to the predicted climate warming. Bering Sea & Aleutian Islands - Climate and Oceanography North Pacific Meets the Bering Sea: Transport through Amukta Pass Carol Ladd, [email protected], NOAA/PMEL Phyllis Stabeno, [email protected], NOAA/PMEL The Aleutian Passes are the conduit by which North Pacific waters influence the Bering Sea. Amukta Pass contributes an average of more than 4 Sv of transport into the Bering Sea, comprising the major source for the Aleutian North Slope Current and the Bering Slope Current. The flow through Amukta Pass carries heat and freshwater in comparison to the mean conditions of the southeast Bering Sea. The deep, subsurface temperature maximum in the Bering Sea is maintained by this inflow. In addition, mixing within the pass results in fluxes of nutrients into the Bering Sea surface waters, contributing to productivity in the Green Belt and over the shelf. Four moorings, spanning the width of Amukta Pass, have been deployed since 2001. This time series, although not continuous in time, is becoming long enough to evaluate transport variability. A seasonal cycle with maximum transport in winter and minimum transport in fall matches that of the Aleutian North Slope Current. Variability in the transport through Amukta Pass, along with its driving mechanisms and consequences for the southeast Bering Sea will be discussed. Bering Sea & Aleutian Islands - Ecosystem Perspectives Macroecological Patterns in North Pacific Ecosystem Dynamics: Spatio-Temporal Co-Variation in Upper and Lower Trophic Level Diversity and Productivity from Canada to Japan Mike F. Henry, [email protected], Farallon Institute for Advanced Ecosystem Research Sonia D. Batten, [email protected], Sir Alister Hardy Foundation for Ocean Science K. David Hyrenbach, [email protected], University of Washington Ken H. Morgan,
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