Santa Barbara Coastal LTER & California's Marine Protected Areas

Santa Barbara Coastal LTER & California’s Marine Protected Areas

Dave Siegel University of California, Santa Barbara

Santa Barbara Coastal LTER Santa Barbara Coastal Long Term Ecological Research

• ~ 10,000 km2 • Steep coastal mountains • Small estuaries • Shallow rocky reefs • Deep ocean basin • Offshore islands

• Mediterranean climate • Strong ENSO signal • Major biogeographic boundary Giant Kelp Forests

• High primary production

• Biological habitat formation

• Support high species diversity

• Complex trophic interactions

• Worldwide distribution on shallow temperate reefs

• High economic importance U.S. West Coast Rockfish

Source: Pacific Fisheries Management Council, 2001 MPA’s in Channel Islands

• State-federal process to implement Marine Protected Areas around the Channel Island National Marine Sanctuary

• Stakeholder driven goals: – protect biodiversity – maintain fishery yields & incomes How a MPA might work

• MPA’s allow adults grow to maturity (especially for sedentary fish & inverts) • Elimination of harvest enables more “natural” communities & food webs to exist • Fecundity often increases with age • Fishery benefits if progeny disperse broadly or adults “spill out” of the MPA How a MPA might work

Spillover Fish(x) MPA

Distance ->

Key: Spatial Management of a Fishery MPA’s Work Within Their Borders

From Halpern [2002] A Benefit of Getting Old & Fat We were victims of public service...

• Six SBC-LTER PI’s served on the Science Panel for the Channel Islands Marine Reserve process • Helped the stakeholder working group arrive on a “preferred alternative” MPA plan • This plan has been implemented by the State Approved Oct. 24, 2002 for state waters Federal approval in the works MPA’s in California

• Marine Life Protection Act (AB993) – Implement a state-wide MPA network – Take a regional approach to siting marine reserves – SBC-LTER participants are part of this process – On hold due to state budget … but it is the law!! What did/will SBC-LTER contribute?

• Local data & expertise – SBC-LTER & its partner programs • Theoretical & synthetic analyses – How big, how many, how connected? – How hard will it be to assess MPA efficiency?? • Next steps – Flow, Fish & Fishing (F3) Biocomplexity Project – MLPA, California-wide MPA designation legislation Fished Organism Life Cycle is Important Dispersal Scales for Marine Organisms

Kinlan & Gaines [2003; Ecology 84: 2007-2020]. Larval Transport Modeling

• Provide a metric for source-to-destination exchanges among nearshore populations

• Incorporate important oceanographic & organism life history characteristics

• Constrain using easily obtained field observations

• Useful for modeling spatial population dynamics

Siegel et al. [2003; Marine Ecology Progress Series 260: 83-96] Larval Transport Modeling

U = 5 ustd = 15 T = 42 T = 56 o f Planktonic larval duration: 6 to 8 weeks 100 : U = 5 cm/s, = 15 cm/s 90 Flow Statistics su N = 5000 80

total settlers= total 1024 =part 5000 20

0 -600 -400 -200 0 200 400 600 800 1000 alongcoast (km) (a,b,c = 84.815 200.39 216.62)

• Many trajectories are simulated to produce the settling probability distribution (the kernel) Regional Scale Self Seeding

What fraction of larvae settle within a region of size L?

Will a MPA seed itself Dd large L small or its surroundings?

Dd Scales as D /L small d L large Will a MPA Retain or Export??

A MPA will retain or export progeny based on the organism’s dispersion scale & the size of the MPA

50% retention

Design for Export

Design for Design D /L~0.5

Conservation d Is a MPA a Source or Sink?

If MPA has L= 10 km,

exports if Dd  5 km

Retains Exports

• A single MPA will be both a larval source & sink • Points to networks of reserves for conservation Reserve Networks

• Conserves organisms with both far & short larval dispersal

• Should contribute to fishery goal as well Approved Oct. 24, 2002 State waters implemented Federal in the works Larval Transport, Time & Fish Stock Uncertainty

• Larval dispersal measured or modeled represents ensemble mean conditions

• The implied time to construct similar mean estimates is 10 to 50 years!!

• However, fish recruitment and fishery management time scales are much shorter Time, continued... • Annual recruitment may be a small sampling of a dispersal kernel (N = 10?, or less!!)

– (300 releases / year) * (10% survival) / (3 day tL)

U = 5 Ustd = 15 T = 14 T = 21 o f • Implies that connections 2

1.8 among sites are stochastic 1.6 1.4 N=5000 & intermittent 1.2 1

0.8 • Critical for assessing the 0.6 total settlers= 13 total =part 100 0.4 “success” of a MPA as a 0.2 0 -100 -50 0 50 100 150 200 250 300 350 fishery instrument alongcoast (km) Invertebrate Settlement – SBC-LTER/PISCO

Ellwood Invert Setttlment Time Series 70

Mytilus Clams (excl razor & HIAARC) any marine snail (excl. veligers, limp) 50 Limpet species Snail veliger any seastar Hiatella arctica

30 # # settlers/deployment

0 160 180 200 220 240 260 280 300 320 JD 2001 Time series sampling – Dt = 2 d Interpreting Settlement Time Series

• Stochastic, quasi-random time series • No correlation of settling among species • Few settlement events for each species

Ellwood Invert Setttlment Time Series • Events are short 70 60

Mytilus Clams (excl razor & HIAARC) any marine snail (excl. veligers, limp) 50 Limpet species Snail veliger any seastar (2 days) Hiatella arctica

30 # # settlers/deployment

0 160 180 200 220 240 260 280 300 320 JD 2001 Implications for MPA Assessment

• MPA affects on fishery yields will be difficult to assess due to inherent recruitment variability • A variable fishery response is expected • Proper MPA assessment needs to be done over some long time (not really known yet)

• Need real predictive tools (including space, dispersal stochasticity, fisherman dynamics, economics, etc.)

Flow, Fish & Fishing - www.icess.ucsb.edu/~davey/F_cubed SBC-LTER & the MPA Process

• Theoretical & synthetic analyses for MPA – How big, how many, how connected? – Assessment of MPA efficiency?? • Other relevant SBC work – Long-term observations of the kelp ecosystem – Terrestrial inputs of nutrients, sediments, etc. • We expect to continue our “broader impacts” contributions as part of the MLPA process Thank You!!