Ecological Risk Assessment – a process for prioritising research and management in diverse and data-limited ecosystems Shane Griffiths, Shijie Zhou, Alistair Hobday and Tony Smith CSIRO Marine and Atmospheric Research SPC workshop 14 June 2010

Ecological Risk Assessment Outline  What is an Ecological Risk Assessment?  Existing risk assessment methods  CSIRO ERA Methodology  Sustainability Assessment for Fishing Effects (SAFE)  Application in Australia’s Northern Prawn Fishery

Ecological Risk Assessment What is an Ecological Risk Assessment?  “An assessment that can determine the risk of a species’ population, assemblage or habitat becoming unsustainable in the long-term due to the effect of a specific perturbation”.  Allows scientists to provide advice to managers about “high risk” species in order to both protect the species & ensure the longevity and profitability of the fishery.

Ecological Risk Assessment Australia’s Northern Prawn Fishery  1 million km 2  115 boats  9 prawn species  t yr -1  AU$80 million yr -1

Ecological Risk Assessment Australia’s Northern Prawn Fishery  100’s of non-target species caught  Byproduct (e.g. squid, scallops, reef fish)  Bycatch (discarded)  30,000 t yr -1 of bycatch discarded, mostly dead.  Introduction of TEDs and BRDs in 2000 to reduce bycatch

Ecological Risk Assessment

 Environment Protection and Conservation Act 1999 in Australia requires export fisheries to demonstrate ecological sustainability  Possible for target species – but 100’s of bycatch species?  All species equal – monitoring is expensive & impractical  Ecosystem models – data intensive & often not species-specific  Ecological Risk Assessment – cost-effective & data-limited

Ecological Risk Assessment Ecological Risk Assessment Methods  Several ecological risk assessment methods developed worldwide  Qualitative – Likelihood-Consequence Analysis, Scale Intensity Consequence Analysis (SICA), Fuzzy Logic Expert System  Semi-quantitative attribute-based methods (e.g. PSA)  Quantitative models – Sustainability Assessment for Fishing Effects (SAFE), and stock assessment models (not often used)

Ecological Risk Assessment CSIRO ERA Methodology

Ecological Risk Assessment Scoping  0 or 1 score given for a range of risk activities  If any activity score is 1, the fishery enters Level 1 analysis Direct impact of Fishing Fishing ActivityScore (0/1) Documentation of Rationale CaptureBait collection0No bait collection occurs Fishing1Capture of organisms due to gear deployment, retrieval and actual fishing. Incidental behaviour0No specific activity identified Direct impact without capture Bait collection0No bait collection occurs Fishing1Organisms may come into contact with TED or net; benthic species may be damaged by net moving over them. Incidental behaviour1Possibly hooking of sharks and hooks remaining in the animal Gear loss1Uncommon but may occur Anchoring/ mooring1Occurs during day light throughout the fishery except the JBG, where fishing usually occurs 24 hrs Navigation/steaming1Continuous searching and trawling during the night, often steaming between locations during the day.

Ecological Risk Assessment Level 1 – Scale Intensity Consequence Analysis (SICA)  Target, bycatch, byproduct, TEP, habitat, community analyses  If a consequence score >3 move to Level 2 - PSA

Ecological Risk Assessment Level 2 Productivity - Susceptibility Analysis (PSA)  Limited data required, can use “guesstimates”  Criteria describe biological, ecological and fishery aspects for every species  Each species is given a rank (1-3) for each criteria  Mortality  Fecundity  Breeding strategy etc  Water column position  Diel behaviour  Locomotion etc

Ecological Risk Assessment Productivity - Susceptibility Analysis Advantages  Conceptually and mathematically simple  Can analyse hundreds of species with limited data  Rapid and cheap assessment using existing information Disadvantages  Relative ranking – are “highest risk” species really at risk?  Thus, cannot demonstrate ecological sustainability of a fishery

Ecological Risk Assessment Level 3 – Sustainability Assessment for Fishing Effects (SAFE)  New model quantifies risk on each species by estimating: 1) the proportion of the population impacted by the fishery 2) Species sustainability using a simple population model  A simple quantitative “filtering” approach to identify any high risk species to monitor

Ecological Risk Assessment SAFE Data Requirements 1.Presence/absence data for each impacted species across entire fishery managed area – fished and unfished areas 2.Susceptibility – the relative susceptibility to capture 3.Escapement - proportion of catch escaping (e.g TEDs, BRDs) 4.Post-capture survival – proportion of catch surviving discard 5.Natural mortality

Ecological Risk Assessment Fishery Impact Component  Where I = proportion of the species population potentially impacted  N F = Number of animals in the “fished area”  N U = Number of animals in the “unfished area”  But how is abundance estimated for low-value bycatch species?

Ecological Risk Assessment A “simple” model  Abundance calculated from presence-absence data in a model incorporating gear-specific detection probabilities and species site occupancy probability. Huh…???

Ecological Risk Assessment Fishery Impact Component  Where F = adjusted proportion of the species population impacted  I = proportion of the species population potentially impacted  q = the relative susceptibility of a species by a particular gear type  Experimental data (Great Barrier Reef)  E = proportion escaping after entering the net (e.g. TED & BRD)  S = proportion of the landed catch surviving discarding  Species-specific data not available for some parameters. Used data from closely related species or “ecomorphotypes”

Ecological Risk Assessment Hypothetical Example  The fishery potentially impacts of fish = 24%  A “catchability” of 0.3 for a trawl reduces impact to 7.2%  TED “escapement” of 50% reduces impact to 3.6%  Post-capture survival of 65% results in final impact of 2.3% White tip shark distributionNPF “Fishery” >5 boat days

Ecological Risk Assessment Population model  Once fishing mortality calculated, the sustainability of the population is estimated using a modified Graham-Schaefer’s production model  Natural mortality used to calculate the maximum sustainable fishing mortality (F MSM ) before the population begins to decline  If fishing mortality exceeds the (F MSM ) reference point, the population is at “high risk” of becoming unsustainable  Management action would then be to remove the risk or monitor the species and apply more rigorous populations models to assess status

Ecological Risk Assessment NPF Teleost Bycatch Results

Ecological Risk Assessment Conclusions  Ecological Risk Assessment can be a rapid and cost-effective way of assessing the risk of anthropogenic activities on marine organisms  CSIRO ERA methodology is a simple method that engages all stakeholders to assess risks  The process is transparent and may increase acceptance of risks and uptake of management measures by stakeholders  New quantitative risk assessment methods (SAFE) can allow fishery managers to more confidently introduce risk mitigation measures  Reduces cost to the fishery to only monitor/manage true “at risk” species

Thank You Contact: Shane Griffiths Phone: Web: