Kevin T. Hill Fisheries Resources Division Southwest Fisheries Science Center

 Historical overview  Sardine population & mgmt since recovery  Stock assessment process  Assessment data  Biology, Fisheries, Surveys  2010 assessment results  Harvest policy & management issues

5-year averages of estimated sardine population biomass, AD ; Age-structured estimates shown in red; Extreme population variability even in absence of fishing; periods of peak abundance ~ years link to environmental forcing is assumed Typical population dynamic for an ‘R-selected’ species: small body, rapid growth, early maturation, high fecundity, short generation time, and the ability to disperse offspring widely Sardine scale-deposition in the Santa Barbara Basin (Soutar & Isaacs 1969; Baumgartner et al. 1992). “Little Ice Age”

Early Sardine Science & Management Intense fishery sampling, ageing with scales and otoliths; Catch-effort studies (lunar-month); Tagging studies (still the best available); Early efforts by CDFG biologists to set caps and limit reduction fishing; Agency responses to declining catch were mixed & conflicting; ‘Marine Research Committee’, later renamed ‘CalCOFI’, was established by CA legislature in 1949 to ‘study the sardine problem’; Actions by the CA legislature were too little and too late to avoid eventual moratorium 23 years after Monterey fishery collapsed CalCOFI Sampling

Tagging ( )

 1980 s :  low abundance, confined to SCA; minor fisheries in SCA & ENS  1990 s :  Expansion offshore and north to Central California;  CCA fishery begins;  Pop’n growth = 33%;  Sardine in OR, WA, and BC  2000 s :  Fisheries in PNW  Seasonal movements N-S, inshore/offshore San Pedro Ensenada Washington Oregon Monterey British Columbia 2000 s 90 s 80 s

Space-time distribution of Pacific sardine subpopulations (Felix-Uraga et al. 2004, 2005) WINTER SPRING SUMMERFALL SPRING

Biology: Age, Growth, Maturity Biology: Age, Growth, Maturity Fishery: Tonnage, Size & Age Composition Fishery: Tonnage, Size & Age Composition Abundance: Resource Survey, CPUE, Age & Size Composition Abundance: Resource Survey, CPUE, Age & Size Composition Population Dynamics Model: Birth, Growth, Reproduction, Death Reconstruct past population trend & productivity. Estimate present abundance for resource managers. Population Dynamics Model: Birth, Growth, Reproduction, Death Reconstruct past population trend & productivity. Estimate present abundance for resource managers. Stock Status Optimum Yield (socioeconomic and ecosystem considerations)

 Fishery Data (tonnage, size, age of removals):  Pacific Northwest (PNW)  Central California (CCA)  Southern California (SCA)  Ensenada (ENS)  Fishery-Independent Data (time series of abundance):  CDFG & SWFSC egg production surveys:  DEPM or TEP time series, depending on adult sampling;  West Coast Sardine Aerial Survey (industry funded):  Current assessment includes estimates for OR-WA region, 2009 & 2010  Assessment Model:  ‘Stock Synthesis’ (Richard Methot, NOAA)  Fully integrated, forward-projecting, length and age-structured, highly flexible

Length-at-ageWeight-at-length

Season 1 (Jul-Dec)Season 2 (Jan-Jun)

Season 1 (Jul-Dec) Season 2 (Jan-Jun)

 Low egg density (P 0 );  Spawning fraction ~10% (≤avg);  Females slightly larger;  SSB total = 105,220 mt;  SSB female = 58,447 mt (0.42);  Lowest DEPM biomass estimate since mid-1990s

DEPM (female SSB) q = TEP (total SSB) q =

 SS model tuned prior to inclusion of aerial est.;  Catchability fixed to q=1;  Length comp fit with dome-shaped selectivity;  Selectivity assumptions not explored during STAR, but inconsistent with PNW fishery selectivity which is fit to asymptotic shape 173,390 mt (0.4)1,236,910 mt (0.9)

537,173 mt

 Independent peer-review (NMFS and PFMC):  Stock Assessment Review Panel (4-5 scientists)  Scientific and Statistical Committee (~16 scientists)  CPS Management Team (agency scientists)  CPS Advisory Subpanel (fishing industry & 1 NGO rep)  Management action:  Pacific Fishery Management Council (PFMC) ▪ adopt assessment; apply harvest formula; allocate by season/sector  NMFS Southwest Region (SWR) ▪ Proposed and final regulations published in Federal Register  Catch monitoring and Enforcement ▪ (CDFG, ODFW, WDFW, NOAA)  Season closure (NMFS-SWR)

Stock biomass (age 1+, mt)Cutoff (mt) Harvest Fraction U.S. Distribution U.S. Harvest for 2011 (mt) 537,173150, ,526 HG 2010 = (BIOMASS 2009 – CUTOFF) FRACTION DISTRIBUTION To determine an appropriate (sustainable) FRACTION value: F MSY = (T 2 )− (T) where T ( o C) is the running average sea-surface temperature at Scripps Pier during the three preceding seasons (July-June), and exploitation FRACTION is bounded between 5% and 15%. Maximum catch allowed = 200,000 mt

Mean three- season SST (°C) at Scripps Equilibrium spawning biomass (mt) Maximum sustained yield (MSY) Spawning biomass at MSY (B MSY )F MSY (%) , , ,700,000156,0001,272, >4,000,000346,0001,819, The spawner-recruit model was used to estimate changes in deterministic maximum sustained yield (MSY) reference points due to changes in environmental conditions associated with three-season SST at SIO, with ° C being the inter-quartile SST range since 1916:

 Sardine will continue to:  have rapid fluctuations in abundance/distribution;  be utilized by predators, including humans.  Researchers and managers will:  have lagged response to changes in the resource;  depend on labor-intensive data collection and time series;  require more funding to ‘do it right’  Approach:  minimize risk through conservative harvest policies;  design surveys & methods applicable to all CPS;  strive for international management agreements