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Status of the California Current System
Background
Highlights/Critical FactorsDecadal ForcingInterannual ForcingStatus: phytoplankton/zooplanktonfish/seabirds+mammalsImportant IssuesPacific Coastal Observing SystemTagging of Pacific Pelagics
Contributors: Bograd, Durazo, Hickey, Huyer, Hyrenbach,Lavaniegos, Mantyla, McKinnell, Perry, Peterson, Ralston, Reiss, Schwing, Stein, Sweetnam, Sydeman, Venrick
California Current System: Background
EnvironmentEnvironment1. Extends 3000 km, Vancouver Island to Baja2. California Current: meandering equatorward flow, carries cool/fresh/oxygenated/
nutrient-rich waters3. California Countercurrent/Davidson Current: weak poleward surface flow,
seasonally-modulated4. California Undercurrent: poleward flow at depth along continental slope5. Strong impacts from regime shifts, El Niño events6. Importance of North Pacific Current bifurcation
BiologyBiology1. High production from coastal upwelling2. Significant commercial nearshore invertebrate populations3. Important groundfish populations on shelf4. Migratory pelagic species: salmon, sardine, hake, herring (north);
anchovy, squid (south)
California Current System: Highlights and Critical Factors
Cool Regime vs. Warm El NiñoApparent regime shift from warm to cool CCS in 1999Strong El Niño in 1997-98; moderate El Niño in 2002-03,with warm SSTs and depressed plankton abundances off CA
Anomalous Subarctic Intrusion into CCS in 2002Subarctic waters detected from Vancouver Island toSouthern CaliforniaEnhanced primary production within nutrient-rich waters;hypoxic event on Oregon shelf
Continued strong upwelling in CCS (since 1999)Decline in California commercial landings, value of some invertebrates and groundfishNew regulations to rebuild overfished rockfish stocks
North Pacific Regime Shifts: State Changes in Forcing
SSTA
SLPA,WindA
“cool” “warm” “cool?”
Peterson and Schwing, 2003
North Pacific Regime Shifts: Take Home Messages
Pan-trophic biological response to regime shifts
Early recognition of shift through physical andbiological indicators leads to better management
BUT … not all regimes are alikeDifferent environmental statesSpatial heterogeneity
Must continue to MONITOR
The Subarctic Intrusion of 2002: Forcing
Southward Ekman transport into NPC;Strong flow in eastern NPC;Strong coastal upwelling;Strong equatorward flow in CCS
Jan-Feb 2002
June 2002
Oct-Nov 2002
SST anomalysurface wind stress anomaly
Murphree et al., 2003
The Subarctic Intrusion of 2002: Effects
Underway fluorescence voltageGLOBEC LTOP, July 2000 vs. July 2002 July 2002 T-S vs. 1961-71 mean
extreme water property anomalies (T, S, O2, NO3) extending 1500 km,enhanced productivity, respiration, benthic hypoxia
Huyer, 2003
CCS Status and Trends: Upwelling
Upwelling Index
downwelling,winter 2002-03
Anomalies
strong spring/summer upwelling (still!)
CCS Status and Trends: ZooplanktonVancouver Island Southern California, Baja
• high biomass in spring 2002(subarctic intrusion)
• low biomass in winter 2003(El Niño)
• changes in zooplankton composition related to climate shifts
• similar trends seen off Oregon• good indicators of climate!
McKinnell/Perry/Venrick
CCS Status and Trends: Fish, Northern CCS
1999 2000 2001Year
0
10
20
30
40
Biomass (tho
W. smeltP. sardineP. herringN. anchovy
SPECIES
• herring spawning increased in 2002 to nearlong-term average
• herring recruitment low when ocean is warm,summer biomass of migratory predators is high
• conditions favorable for herring survival in 2000-01
• good growth conditions for salmon offVancouver Island
British ColumbiaBritish Columbia
• catches of forage fishes have increased steadilyfrom low values in 1999
Washington, OregonWashington, Oregon Bio
mas
sMcKinnell
CCS Status and Trends: California Fisheries
Sweetnam
California fishing ports
Landed over 177,000 metric tons of fish, invertebrates in 2002(-12% from 2001, -28% from 2000)
Preliminary value of US $104 Million (+1% from 2001, -22% from 2000)
Top three grossing stocks: market squid, dungeness crab, sea urchin (followed by chinook salmon, swordfish, Pacific sardine, California spiny lobster, albacore, sablefish, spot prawn)
Higher demand for market squid, dungeness crab
Declines in landings of Pacific mackerel, jack mackerel,northern anchovyFederal, state regulations imposed to rebuild rockfish stocks
Recent Change in the CCS: Seabirds
Seabirds show responseof upper-trophic predators to ocean variability
Subarctic
Subtropical
cool-water species dominatein 1999-2001
high reproductive successfor all species since 1998(Farralons)
warm-water species returnin 2002-03 (El Niño)
Sydeman
California Current System: Issues
The nature of regime shiftsWhat are the mechanisms? Biotic responses?Interactions between decadal and interannual forcingSpatial heterogeneity in amplitude/timing of climate events
Interactions among environmental variability, recruitment fluctuations, fishing pressure
Over-harvest of low-mobility species (abalone, rockfishes)
Interactions between fisheries and marine mammals
HABs increasing in intensity, frequency, duration, location
Need a coordinated, holistic physical/ecosystem monitoringprogram for the CCS PaCOSPaCOS
Pacific Coastal Observing System (PaCOS)(formerly ACCEO – Alliance for California Current Ecosystem Observations)
“A plan for an observing system for the US EEZ of the Pacific Coastthat supports the fishery resources, protected species, andecosystem responsibilities of NOAA Fisheries.”
Chair: William Fox, Office of Science &Technology
Coordinators: John Hunter (SWFSC)and Elizabeth Clarke (NWFSC)
Pacific Coastal Observing System (PaCOS)
NOAA budget initiative for FY06
• monitor pelagic ecosystem• govt/academic alliance• applied, long-term science
goals• sustain physical/biological
time series• gradual expansion of
monitoring• understand dynamics of CCS
and its populations; interannual-decadal change
• NOAA Fisheries contributionto IOOS
Tagging Of Pacific Pelagics• Tag TOP Predators in the eastern North Pacific
2003- 2006 (~5000 individuals)• Develop tools for the integration of biological and
physical oceanographic data for furthering ocean exploration
• Discover the “Hot Spots” & “MigratoryHighways” of the Eastern North Pacific for large pelagics
TOPP Species• Air Breathing Vertebrates
– Leatherback Turtle– Loggerhead Turtle– Black footed Albatross– Laysan Albatross– Elephant Seals– California Sea Lions– Blue,Fin & Humpback
Whales– Sperm whale– Shearwaters
••Fish, Shark and SquidFish, Shark and Squid––Bluefin TunaBluefin Tuna––YellowfinYellowfin TunaTuna––Albacore TunaAlbacore Tuna––White shark White shark ––Mako Mako sharkshark––Salmon sharkSalmon shark––Thresher sharkThresher shark––Blue SharkBlue Shark––DosidicusDosidicus squidsquid––MolaMola––SwordfishSwordfish