U.S. Pacific Coast Krill (Euphausiids)

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1 Agendum E.3.b Supplemental NMFS PowerPoint Presentation September 2004 U.S. Pacific Coast Krill (Euphausiids) Prepared by: Susan E. Smith Roger Hewitt NMFS Southwest Fisheries Science Center, NOAA 8604 La Jolla Shores Drive, La Jolla, CA

2 Species of Concern Only two likely to be targeted by a fishery (because abundant and known to form dense surface swarms): Euphausia pacifica Thysanoessa spinifera Six others common but either do not swarm near the surface, or occur further to the south most years (e.g. Nyctiphanes simplex).

3 Euphausia pacifica Possibly the most abundant off our coast Strong vertical migrator-- surface at night descending to ~ m during day but can also swarm at surface in day. Adult size: to mm (< 1 )

4 Distribution

5 E. pacifica, continued I year life span off California (Brinton 1976) Continuous recruitment with peaks during upwelling periods. (Brinton 1976) Important prey of whales, fish, squid and birds.

6 Coastal/neritic; occurs in waters less than 100 m deep. Thysanoessa spinifera Commonly forms dense daytime surface swarms. Size to 30 mm (1 ¼ )

7 Distribution

8 T. spinifera, continued Longer life span; estimated three years. More discrete spawning season (May-July off California at upwelling peak). Biomass likely under-estimated adults good at avoiding nets. Also important forage.

9 Both Cool-water subarctic species. Biomass plummets extreme warm water years, but resilient, can rebound from El Niño lows. BUT. No comprehensive coast-wide biomass, MSY or OY estimates available. No annual predator consumption estimates available, but lots on presence in diet of a great variety of California Current fishes, birds and whales.

10 Biomass Estimates ESTIMATED BIOMASS/DENSITY Very rough E pacifica estimate from NMFS (1976) of probably over 100 million tons off California. Thought to be based on Brinton s (1976) density estimates (i.e., avg. 10-1,000 mg wet weight of E. pacifica beneath 1m 2 of sea off California). Above avg. densities extrapolate to ~12,350 mt to 1.2 million mt for SCB alone. BUT from a cool-water (favorable) period, so represents upper range. DECADAL BIOMASS TRENDS ( ) (Brinton and Townsend 2003) E. pacifica and T. spinifera peak biomass collapsed as much as 90% during extreme El Niño periods, (less so in central vs. southern California), but populations rebounded quickly in succeeding cool years. Densities similar for E. pacifica in central and southern California; tho T. spinifera overall appears more abundant in north.

11 Partial List of Predators Market squid Pacific hake Pacific herring Spiny dogfish Blue shark Sablefish Myctophids Jack mackerel Pacific mackerel Pacific sardine Numerous Sebastes species (e.g., boccacio, widow, yellowtail rockfishes) Pacific sanddab Slender sole Pacific halibut Chinook salmon Coho salmon Albacore Cassin s auklet Marbled murrelets Western gull Sooty shearwater Common murre Humpback whale Blue whale Grey whale

spring winter California Blue Whale Seasonal Movements Calving: December - February Weaning: June - August

12 Krill Presence in NOAA Marine summer Sanctuary Waters Blue and fin whales have been documented feeding on layers of krill in the vicinity of the Channel Islands, Monterey Bay, Gulf of Farallones and Cordell Bank Marine Sanctuaries. spring winter California Blue Whale Seasonal Movements Calving: December - February Weaning: June - August (Calimbokidus, Gendron, Croll, Tershy) Monterey Bay Blue Whale Sightings N=411 sightings (Black, Ternullo, Baldridge, Croll)

13 Presence in Marine Sanctuary Waters, Continued High krill densities associated with bathymetric features that modify ocean currents (e.g., banks, continental shelves around islands, submarine canyons WHAPS96 Surveys B and C - July 17-21, Volume Backscattering Strength at 200 khz Integrated from 5m to 250m depth Integrated volume backscattering strength (m 2 nm -2 ) of krill near the Santa Barbara Channel Islands, July 1996

Presence in NOAA Marine Sanctuary Waters,

Blue whale dive tracks (black) following

14 Presence in NOAA Marine Sanctuary Waters, Continued Whales and seabirds aggregate near these features to take advantage of high densities of krill. Blue whale dive tracks (black) following day/night movements of krill (red) on shelf break near Channel Islands, California.

15 North Pacific Krill Fisheries Product used in fish culture; aquarium/ pet food; human consumption. Frozen; freezedried. California imposed ban on krill fishing in state waters in 2000; Oregon in Washington prohibits landing and sale of commercial quantities of krill. Fisheries for E. pacifica exist in Japan and British Columbia

16 British Columbia Fishery Began as experimental fishery Strait of Georgia in 1972 Quotas established 1976 in response to concerns about harvesting an important forage species, and bycatch of juvenile salmon. Annual catch set at 500 t (3% of estimated annual consumption of krill by all predators in the Strait). Seasonal closures enacted to limit bycatch. Limited entry in 1993 to 18 fisher licenses (< 10 vessels now active) 1995 workshop held at U. of B.C. on Harvesting Krill: Ecological Impact, Assessment, Products and Markets. Quota of 500 t remains fixed; Canada does not support further development of fisheries on forage species such as krill.

17 Tentative Conclusions Need estimates annual consumption by all predators Need annual regional biomass estimates of both species (with range covering different oceanic regimes). Possible that krill surplus off California (beyond predator needs) could support a small, quota-managed fishery in high production (cold-water) years, but not likely in warmwater years when forage is typically scarce for predators. Other factors, such as bycatch, should also be considered A background paper on krill has been prepared and is included in Council briefing materials.

18 Acknowledgements Ed Brinton and Annie Townsend, Scripps Institution of Oceanography Michele Robinson Culver and Greg Bargmann, WA Dept Fish &Wildl. Jean McCrae, Oregon Dept. Fish & Wildlife Keith Sakuma, NMFS, Santa Cruz, CA

20 Krill Presence in NOAA Marine summer spring Sanctuary Waters Blue and fin whales have been documented feeding on layers of krill in the vicinity of the Channel Islands, Monterey Bay, Gulf of Farallones and Cordell Bank Marine Sanctuaries. winter California Blue Whale Seasonal Movements Calving: December - February Weaning: June - August (Calimbokidus, Gendron, Croll, Tershy) Monterey Bay Blue Whale Sightings N=411 sightings (Black, Ternullo, Baldridge, Croll)

MANAGEMENT OF KRILL AS AN ESSENTIAL COMPONENT OF THE CALIFORNIA CURRENT ECOSYSTEM

MANAGEMENT OF KRILL AS AN ESSENTIAL COMPONENT OF THE CALIFORNIA CURRENT ECOSYSTEM AMENDMENT 12 TO THE COASTAL PELAGIC SPECIES FISHERY MANAGEMENT PLAN ENVIRONMENTAL ASSESSMENT, REGULATORY IMPACT REVIEW