Fishery Management • Fishing is extractive – Removes choices organisms - “fine-ing” – Changes food web structure • The human condition provides little incentive to.
Download ReportTranscript Fishery Management • Fishing is extractive – Removes choices organisms - “fine-ing” – Changes food web structure • The human condition provides little incentive to.
Fishery Management • Fishing is extractive – Removes choices organisms - “fine-ing” – Changes food web structure • The human condition provides little incentive to maintain “sustainable stocks” • Need way to control ourselves… Fisheries by Their Nature are Extractive; They Alter the Natural Environment anthropogenic effect The objective of fisheries management is to achieve a high level of sustainable yield Maximum Sustainable Yield (MSY) BMSY? 300 Sustainable Yield 250 200 150 100 50 no fish no fishing 0 0 20 40 60 Relative Stock Size 80 100 Under exploitation, natural populations decline in abundance to a new equilibrium Yield From Virgin Population for Fixed F 300 Rate of Fishing 250 0.02 0.05 0.10 0.15 0.50 MSY Yield 200 150 100 50 0 1970 1975 1980 1985 Time 1990 1995 2000 The objective of fisheries management is to achieve a high level of sustainable yield Maximum Sustainable Yield (MSY) BMSY? 300 Sustainable Yield 250 200 150 100 50 no fish no fishing 0 0 20 40 60 Relative Stock Size 80 100 A Bioeconomic MSY A Bioeconomic MSY • Considering costs lowers sustainable yields • MEY < MSY Fish Management • Objectives are to maintain sustainable maximum yields (or revenues) • Harvest costs are sometimes considered (especially related to new regulation) • Conservation is not (often) considered • Nor are food webs (management is single species) • Hard part is to figure out the proper harvest effort that produces a MSY The Magnuson-Stevens Fishery Conservation and Management Act (MSFCMA) as Amended in 1996 “The policy of the Congress in this Act is to assure that the national fishery conservation and management program utilizes, and is based upon, the best available scientific information…” 16 U.S.C. 1801 M-S Act, Section 2, 101-627, 104-297 Recent Developments • The Magnuson-Stevens Fishery Conservation and Management Act of 1976 was reauthorized by Congress in 1996 and was implemented nationally in 1997. Reauthorized this year. • 2003 legislation requires Fishery Management Councils nationwide to establish biomass-based targets and thresholds for all actively managed stocks Recent Developments • On January 12, 2007, President Bush signed the Magnuson-Stevens Fishery Conservation and Management Reauthorization Act of 2006. • Mandates the use of annual catch limits & accountability measures to end overfishing • Provides for market-based fishery management through limited access, bycatch restrictions, improved role of science & calls for increased international cooperation. • http://www.nmfs.noaa.gov/msa2007/ What is the Pacific Fishery Management Council? PFMC Region • Responsible for California, Oregon, and Washington EEZ waters (FEDERAL!!) • Established with implementation of original MSFCMA of 1976 • Draft Fishery Management Plans including salmon, highly migratory, groundfish, and coastal pelagics. • Nearshore species - State F&G • All regulations are ultimately approved by National Marine Fisheries Service (NMFS) Who & Where of Fishery Management State waters < 3 nmi Fed waters > 3 but < 200 nmi (EEZ) Complete Marine Protected Area Network For the Channel Islands National Marine Sanctuary Final Network of MPAs, Oct 2007 What is the process for regulating fishery harvests at the PFMC? Stock Assessment Team Stock Assessment Exploitable Biomass Pacific Fishery Management Council “Wall of Science” science review Harvest Policy Allowable Biological Catch (ABC) Socioeconomic, Allocation, and Other Issues Optimum Yield (OY) OY < ABC This is now a three meeting process, with a five month notice and comment period, to be conducted once every 2 years!! Promulgate Regulations Process must be transparent for all parties Stock assessments form the basis of all fishery management Landings by Gear Type 1. commercial Life History Information 2. recreational growth, maturity, etc. Fishery Dependent Information (logbook data, discards, etc.) Stock Assessment (statistical model) Age/Length Compositions 1. commercial 2. recreational Fishery Independent Surveys (shelf & slope trawl surveys, etc.) Biomass and Recruitment Science Review Harvest Policy Allowable Biological Catch (ABC) Optimum Yield (OY) Fish Management • Instruments for setting Optimum Yield Harvest quotas, trip limits, limited entry, seasons, taxes on landings, ITQ’s, MPA’s, … • Each has advantages • Each requires knowledge of “excess” fishery production Fish Recruitment Harvest • Recruits are fish at harvestable age/size Reproductive Adults Eggs/Larvae Harvestable Size/Age Recruitment Juveniles Immature Adults Curvature in the spawner-recruit curve controls fishery productivity Some Possible Spawner-Recruit Curves 1.40 Recruitment 1.20 high productivity/resilience/steepness 1.00 0.80 replacement line 0.60 0.40 0.20 low productivity/resilience/steepness 0.00 0.00 0.20 0.40 0.60 0.80 Spawning Biomass 1.00 1.20 Bocaccio (MacCall et al. 1999) Recruits (x 1000) 50,000 40,000 30,000 Some Real “Data” 20,000 10,000 0 0 2,000 4,000 6,000 8,000 10,000 12,000 Spawning Output Pacific whiting (Dorn et al. 1999) 14 “Noise” makes “steepness” difficult to measure Recruits (x 1000) 12 10 8 6 4 2 0 0.0 0.5 1.0 1.5 2.0 Female Spawning Biomass 2.5 3.0 Fishery Management Plan for Pacific Sardine • FMP needed to regulate all fisheries • Gives the Allowable Biological Catch (ABC) • Components include: stock biomass, recruitment, egg production, size/age structure, spatial extent, SST, … • Fishery dependent & independent data Fishery Management Plan for Pacific Sardine • A coastal species that forms large schools • Feed on zooplankton & large phytoplankton • Oviparous, with pelagic eggs, and pelagic larvae • Matures in ~2 years & Can live up to 25 years • Population doubling time 1.4 to 4.4 years • Up to 16” long (mature at ~9”) • Northward migrations early in summer & south in autumn Chavez et al. [2003] paper in readings Fishery Management Plan for Pacific Sardine Fishery Management Plan for Pacific Sardine • FMP needed to regulate all fisheries • Gives the Allowable Biological Catch (ABC) • Components include: stock biomass, recruitment, egg production, size/age structure, spatial extent, SST, … • Fishery dependent & independent data Pacific Sardine Egg Production Relative abundance of sardine eggs in CalCoFI larval tows Spawning Biomass from Egg Obs Sardine Stock Area from Surveys Abundance of Pre-Adults Scripps Pier SST Biomass of >1y Sardines • These data were used with an age-structured stock assessment model to predict stock biomass & recruitment Recruitment of Sardines • These data were used with an age-structured stock assessment model to predict stock biomass & recruitment Harvest Policy for Pacific Sardines • U.S. harvest guideline for 2003 • Harvest = (TOTAL_STOCK_BIOMASS - CUTOFF) * FRACTION * US_DISTRIBUTION • CUTOFF = minimal allowable biomass with harvest • FRACTION = 5 to 15% depends on SST (f(PP)!!!) • US_DISTRIBUTION = fraction total harvest in U.S. EEZ Biomass of >1y Sardines Pacific Sardine Quotas & Landings Pacific Sardine Landings Fishery Management Plan for Pacific Sardine • Harvest guidelines require estimates of stock biomass & recruitment • Components include: stock biomass, recruitment, egg production, size/age structure, spatial extent, SST, … • Fishery dependent & independent data are used