Towards Sustainable Multispecies Fisheries in the Florida Coral Reef Ecosystem Jerald S. Ault University of Miami Rosenstiel School of Marine and Atmospheric Science
Southern Florida coral reefs generated 71 thousand jobs and $6 billion US in economic activity in 2001! They also contributed to the designation of Florida as fishing capital of the world by the state legislature. These ecosystem goods and services, however, are threatened by increased exploitation and environmental changes from a rapidly growing regional human population.
Today I will briefly describe progress and provide 3 examples: Expanded stock assessment capabilities spatial & multispecies. Optimized sampling with new length-based framework. Innovative models to encompass complex biological dynamics of fish stocks and broad range of environmental and human impacts.
(A) (B) (C) (D)
Coastal Bays to Coral Reefs (CBCR) Everglades Restoration Freshwater Miami Port of Miami Gulf Stream Straits of Florida Mangrove Biscayne Barrier Patch Barrier Coral Pelagic Marsh Bay Islands Reefs Reef Environment MANGROVES SEAGRASSES PATCH REEFS BANK and DEEP TERRACE REEFS
Florida s Human Population Growth 2nd World War
Commercial Landings 4000 3500 Nassau Grouper (Cuba) Catch (mt) 3000 2500 2000 1500 1000 500 0 1200 1000 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 Yellowtail Snapper All Groupers (Florida) Black Grouper (FL) Catch (mt) 800 600 400 200 Gray Snapper 0 1955 1965 1975 1985 1995 2005 Commercial: TIP, Logbook, Recreational: MRFSS, Creel (BNP, ENP), Headboats
Serial Overfishing in the Florida Keys 100 % Spawning Potential Ratio 90 80 70 60 50 40 30 20 GROUPERS Overfishing (30% SPR) SNAPPERS GRUNTS 10 0 black red graysby coney gag nassau yellowfin yellowmouth red hind rock hind scamp snowy speckled hind yellowedge warsaw jewfish hogfish gray mutton yellowtail schoolmaster blackfin cubera dog lane black red sailor s choice barracuda silk vermillion bluestriped white tomtate margate Exploited Coral Reef Fishes Ault, J.S,, Bohnsack, J.A., and G.A. Meester. 1998. Fishery Bulletin 96:395-414 (Best Publication Award & NOAA Certificate of Achievement 2002)
Systems Science Analysis Framework Data Acquisition Population Dynamics Habitats Bioeconomics Coral Reef Ecosystem Model Building Physical Biological Humans Habitats Human-Fishery Sector Fishery Resource Risk Assessment
Bohnsack Method RVC Stationary Cylinder (Reef Fish Visual Census)
Patchy hard-bottom Patch reefs Pinnacles Low Degree of Patchiness High Low-relief spur & groove Low-relief hard-bottom Rocky outcrops Medium-profile reef High-relief spur & groove Reef terrace Low Vertical Relief High
Frequency 0.7 0.6 0.5 0.4 0.3 0.2 Bay Gray Snapper Inshore Reefs Offshore Reefs 0.1 0 Survey Error (%CV) 100 80 60 40 20 3 6 9 12 15 18 21 24 27 30 33 36 39 42 45 60 YOY Juveniles Adults L 1 yo m L c Length (cm) Yellowtail Snapper Gray Snapper 0 1979 1984 1989 1994 1999
RVC Fishery-independent data for Yellowtail snapper Fishery-dependent data range
Reef Fish Recruitment 8 Yellowtail Snapper 2.00E-01 Black Grouper 6 4 2 0 1975 1980 1985 1990 1995 2000 2005 1.60E-01 1.20E-01 8.00E-02 4.00E-02 0.00E+00 1975 1980 1985 1990 1995 2000 2005 8.00E+00 7.00E+00 Gray Snapper 6.00E+00 5.00E+00 4.00E+00 3.00E+00 2.00E+00 1.00E+00 0.00E+00 1975 1985 1995 2005 7.00E-01 6.00E-01 5.00E-01 4.00E-01 3.00E-01 2.00E-01 1.00E-01 0.00E+00 Gray Angelfish 1975 1980 1985 1990 1995 2000 2005 YEAR
3.50E+07 3.00E+07 Yellowtail Snapper 6.00E+05 5.00E+05 Black Grouper 2.50E+07 4.00E+05 2.00E+07 3.00E+05 Population Abundance 1.50E+07 1.00E+07 5.00E+06 0.00E+00 1975 1980 1985 1990 1995 2000 2005 5.00E+07 4.50E+07 4.00E+07 3.50E+07 3.00E+07 2.50E+07 2.00E+07 1.50E+07 1.00E+07 5.00E+06 Gray Snapper 2.00E+05 1.00E+05 0.00E+00 1975 1980 1985 1990 1995 2000 2005 2.50E+06 2.00E+06 1.50E+06 1.00E+06 5.00E+05 Gray Angelfish 0.00E+00 0.00E+00 1975 1980 1985 1990 1995 2000 2005 1975 1980 1985 1990 1995 2000 2005 YEAR
Non-Exploited Species 2.00E+06 1.50E+06 Spotfin butterflyfish 1.00E+06 5.00E+05 Bicolor damselfish Population Abundance 0.00E+00 1975 1980 1985 1990 1995 2000 2005 3.50E+08 3.00E+08 2.50E+08 2.00E+08 1.50E+08 1.00E+08 5.00E+07 0.00E+00 1975 1980 1985 1990 1995 2000 2005 Stoplight parrotfish 1.60E+07 1.40E+07 1.20E+07 1.00E+07 8.00E+06 6.00E+06 4.00E+06 2.00E+06 0.00E+00 1975 1980 1985 1990 1995 2000 2005 Year
Average Size (mm) 900 800 700 600 500 400 300 Black Grouper Reef Fish Visual Census (RVC) 1975 1980 1985 1990 1995 2000 2005 Average Size (mm) 450 430 410 390 370 350 330 310 290 270 250 Yellowtail Snapper Headboat Survey Minimum Size L c 1975 1980 1985 1990 1995 2000 2005 440 420 Gray Snapper 500 Hogfish Average Size (mm) 400 380 360 340 320 300 280 Average Size (mm) 450 400 350 300 260 240 250 1975 1980 1985 1990 1995 2000 2005 1975 1980 1985 1990 1995 2000 2005 Year
(A) (B) Average Size (mm) Florida Hogfish 500 450 400 350 300 250 200 150 100 50 0 1975 1980 1985 1990 1995 2000 2005 Year
(A) (B) (C) Average Size in the Exploitable Phase (FL cm) 450 400 350 300 250 200 150 100 50 0 Florida Hogfish RVC MRFSS 1975 1980 1985 1990 1995 2000 2005 450 400 350 300 250 200 150 100 RVC Biscayne National Park 50 0 1975 1980 1985 1990 1995 2000 2005 450 400 350 300 250 200 150 100 RVC Headboats 50 0 1975 1980 1985 1990 1995 2000 2005 Year
(A) 0.15 0.10 Minimum Size (12 ) Florida Hogfish 1984 N = 533,333 0.05 (B) Frequency 0.00 0.15 0.10 0.05 1 6 11 16 21 26 31 36 41 46 51 56 61 66 71 1994 N = 764,935 (C) 0.00 0.15 0.10 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 2001 N = 3,958,519 0.05 0.00 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 Fork Length (cm)
Maturation Function Growth Function Mature Females Eggs Larvae Juveniles Recruitment Function Copulation Function Hermaphroditism Function Mature Males Maximum Size-Age Competition Function Movement/Migration Function Natural Mortality Function Fishing Mortality Function Natural Deaths Physiological Predation Rec & Comm Yields Fishery Deaths Bycatch Catch & Release Conceptual overview of the REEFS length-based age- and sex-structured population simulation model used for reef fish stock assessment in the Florida coral reef ecosystem.
Hogfish Frequency 0.04 0.03 0.02 0.01 F = F = 0 0.00 764 734 704 674 644 614 584 554 524 494 464 434 404 374 344 314 284 254 224 194 164 134 Frequency 0.06 0.04 0.02 Length (mm) F = F msy =0.13 Juvenescense 0.00 764 734 704 674 644 614 584 554 524 494 464 434 404 374 344 314 284 254 224 194 164 134 Length (mm) 0.12 0.10 F = F 2001 F = F 2001 = 0.5 Frequency 0.08 0.06 0.04 0.02 0.00 134 164 194 224 254 284 314 344 374 404 434 494 464 Length (mm) 524 584 554 614 644 674 704 734 764
250000 Stock Synthesis Modeling Catch (kg) 200000 150000 100000 Use of Maximum Likelihood Estimators with Bayesian Statistics 50000 0 1980 1985 1990 1995 2000 2005 Crec Obs C comm Obs CpredRec CpredComm Alternative estimates of current F Profile Likelihood for B(0) Relative likelihood 1.20E+00 1.00E+00 8.00E-01 6.00E-01 4.00E-01 2.00E-01 0.00E+00 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 Current F Relative Likelihood 1.20E+00 1.00E+00 8.00E-01 6.00E-01 4.00E-01 2.00E-01 0.00E+00 0 100000 200000 300000 400000 500000 600000 700000 800000 Initial Population Biomass B(0) (kg x100000) Likelihood profiles to express parameter uncertainty via MLE criterion.
Higher-Order Structured Stock Synthesis Modeling predicted vs observed survey indices 0.500 Index value (fish/177m2) 0.450 0.400 0.350 0.300 0.250 0.200 0.150 0.100 0.050 0.000 Yield (kg) 1975 1980 1985 1990 1995 2000 2005 year RVC juv pred RVC juv RVC exploited pred RVC exploited 300000 250000 200000 150000 100000 50000 0 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 Fishing mortality rate Average Size (FL) in 500 450 400 350 300 250 200 150 100 RVC Stock Synthesis 50 0 1975 1980 1985 1990 1995 2000 2005
Florida Hogfish Cross-Validation Study 2.50 Fishing Mortality Rate 2.00 1.50 1.00 0.50 0.00 1978 1983 1988 1993 1998 2003 Age-structured SS Continuous SS Lbar RVC aspic
(A) 1.4 Fishing Mortality Rate 1.2 1.0 0.8 0.6 0.4 0.2 Commercial Recreational 0.0 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 (B) Percent of Total Fishing Mortality 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Recreational Frec Fcomm Commercial 1975 1980 1985 1990 1995 2000 2005 Recr F Comm F
Figure 6
New Sustainability Criteria 16 14 Scamp Snowy grouper F/Fmsy 12 10 8 6 4 2 0 Yellowfin grouper Yellowedge grouper Red snapper Overfishing Schoolmaster snapper Silk snapper Vermillion snapper Hogfish Tomtate Red grouper Warsaw grouper White grunt Mutton snapper Gag grouper Black grouper Yellowtail snapper Coney Gray snapper Cubera Yellowmouth grouper Goliath grouper Black Lane Dog Margate Rock Hind Speckled Hind 0.00 0.20 0.40 0.60 0.80 1.00 1.20 B/Bmsy snapper Nassau Blackfin snapper Sailor s choice Graysby Bluestriped MSY Target Red Hind
Scenario Testing - CBCR Model Two dimensional spatial patch interaction model used to simulate fish (predator)-shrimp (prey) community dynamics.
Predator Prey
Biophysical Dynamics
Summary Systems Science cost-effective and precise! Higher resolution of habitat distribution. Integration of FI & FD survey technologies. Spatial growth rate potential (EFH, MPAs). Fishery science framework improves understanding of impacts from fishery extraction, ecosystem alterations, and natural oceanographic variability on the dynamics of exploited fish stocks.