APPENDIX D Ecosystem Considerations for 2000 Reviewed by The Plan Teams for the Groundfish Fisheries of the Bering Sea, Aleutian Islands, and Gulf of Alaska Edited by Pat Livingston Resource Ecology and Ecosystem Modeling Program Resource Ecology and Fisheries Management Division Alaska Fisheries Science Center 7600 Sand Point Way NE Seattle, WA 98115 With contributions by Alaskan Native Communities, Paul Anderson, Ric Brodeur, Cathy Coon, Dave Fluharty, FOCI, Lowell Fritz, Sarah Gaichas, Jawed Hameedi, Jon Heifetz, Jerry Hoff, Jim Ianelli, Jim Ingraham, Jesus Jurado-Molina, K Koski, Pat Livingston, Bob McConnaughey, Glenn Merrill, Franz Mueter, NMFS-NMML, Joe Terry, USFWS, Ivan Vining, Gary Walters, Dave Witherell November 1999 ECOSYSTEM CONSIDERATIONS –2000 TABLE OF CONTENTS SUMMARY OF TRENDS AND RESEARCH RECOMMENDATIONS...................................................3 INTRODUCTION.........................................................................................................................................9 WHAT’S NEW IN ECOSYSTEM-BASED MANAGEMENT? ...............................................................10 ICES/SCOR Symposium on Ecosystem Effects of Fishing ...................................................................10 Report of the NMFS Ecosystem Advisory Panel....................................................................................11 ECOSYSTEM STATUS INDICATORS....................................................................................................13 Physical Environment .............................................................................................................................13 Ecosystem Indicators and Trends Used by FOCI...............................................................................13 Summer bottom and surface temperatures- Eastern Bering Sea.............................................................21 Habitat.....................................................................................................................................................25 Indices of contaminant levels in sediments, groundfish and their prey..............................................25 Bottom Habitat Composition in the eastern Bering Sea.....................................................................31 Progress Report on Essential Fish Habitat Research ..............................................................................33 Current Research on the Effects of Fishing Gear on Seafloor Habitat in the North Pacific...................38 Zooplankton, Chlorophyll and Nutrients ................................................................................................46 Gulf of Alaska ....................................................................................................................................46 Bering Sea ..........................................................................................................................................47 Forage Fish..............................................................................................................................................48 Gulf of Alaska ....................................................................................................................................48 Bering Sea ..........................................................................................................................................53 Other Species ..........................................................................................................................................53 Gulf of Alaska ....................................................................................................................................53 Eastern Bering Sea..............................................................................................................................58 Benthic Communities and Non-target fish species .................................................................................60 Gulf of Alaska ....................................................................................................................................60 Eastern Bering Sea..............................................................................................................................65 Marine Mammals....................................................................................................................................68 Seabirds...................................................................................................................................................72 Ecosystem or Community Indicators and Modeling Results..................................................................89 Present and Past Ecosystem Observations – Local and Traditional Knowledge................................89 Spatial and temporal patterns in the Gulf of Alaska groundfish community in relation to the environment........................................................................................................................................93 Multispecies Forecasting of the Effects of Fishing ..........................................................................102 Ocean Surface Current Modeling Update.........................................................................................109 ECOSYSTEM-BASED MANAGEMENT INDICES AND INFORMATION........................................110 Ecosystem Goal: Maintain Diversity ...................................................................................................110 Time Trends in Bycatch of Prohibited Species ................................................................................110 Time trends in groundfish discards...................................................................................................112 Ecosystem Goal: Maintain and Restore Fish Habitats..........................................................................113 Areas closed to bottom trawling in the EBS/AI and GOA...............................................................113 Groundfish fishing effort in the eastern Bering Sea .........................................................................115 Groundfish fishing effort in the Gulf of Alaska and Aleutian Islands..............................................118 Ecosystem Goal: Sustainability (for consumptive and non-consumptive uses) ...................................121 Trophic level of the catch .................................................................................................................121 Status of groundfish, crab, scallop and salmon stocks .....................................................................123 Ecosystem Goal: Humans are part of Ecosystems................................................................................123 Fishing overcapacity programs.........................................................................................................123 Groundfish and crab fleet composition.............................................................................................125 LITERATURE CITED .............................................................................................................................127 2 SUMMARY OF TRENDS AND RESEARCH RECOMMENDATIONS Summary of Ecosystem Status and Trend Indicators Physical Environment Indicators: North Pacific climate indicators - Winter sea level pressure indicators show there was warmer winters in the late 70’s and early 80’s but a minor shift around 1989 to colder winters. 1998 showed a warming and 1999 a cold winter. Spring North Pacific index values – high values mean increased surface temperature due to solar heating. This index has been increasing through the late 70’s but saw a major decrease in 1998. GOA pollock precipitation-based and wind- mixing based survival indices are still high EBS ice cover still appears lower than the 70’s. EBS summer bottom and surface temperatures were colder than usual in 1999, particularly in the shallow, inner shelf areas and southern middle shelf. There were some indications of differences in distribution and catchability of various groundfish species due to the cold conditions in 1999. Indicators seem mixed with regard to whether we are moving into a different climate state. There is presently a lack of ability to predict the short-term (3-5 years) and longer-term climate state for the North Pacific. Contaminants: GOA mussel watch site – contaminants are generally low except for some metals. In some cases metal concentrations exceed 85th percentile values of the nationwide database for chromium, nickel, and selenium. Benthic surveillance project of contaminants in bottom dwelling fish and sediments – data from sites in Alaska are extremely limited and unable to make any conclusions at this time. Arctic regional assessment of radionuclides and contaminants indicates low anthropogenic radionuclide activity in the US Arctic but radionuclides are pervasive – indicating global fallout as likely the predominant and perhaps only source. Subsistence foods from marine food chains, such as seals and bowhead whales contain very small and nearly negligible amounts of radiation. Toxic elements such as arsenic, chromium, coper and nickel show generally elevated levels in eastern Bering Sea and Beaufort Sea sediments. There appears to be no anthropogenic sources for these elements in these regions. The elevated levels are attributed to enriched source rocks and regional mineralogy. There