Science Advisory Report  2015/037

Application of an ecological risk assessment framework to inform ecosystem-based management for SGaan Kinghlas-Bowie Seamount and Endeavour Hydrothermal Vents Marine Protected Areas

Summary

• Two applications of the scoping phase and the semi-quantitative Level 2 ecological risk assessment framework (ERAF) methodology (DFO 2012) were reviewed at a Regional Peer Review meeting in 11-13 February 2014 and 13 March 2015. Cumulative risk to significant ecosystem components (SECs) and the potency of stressors across SECs were estimated in the Endeavour Hydrothermal Vents (EHV) and SGaan Kinghlas-Bowie Seamount (SKB) Marine Protected Areas (MPAs) and were used to develop ranked lists of SECs and identify the activities/stressors driving those risks.
• Both applications of the Level 2 ERAF applied five important modifications that were addressed in the review:
1. uncertainty associated with each term in the risk equation was incorporated into the score as recommended by DFO (2014);
2. a bin for zero or negligible scores in resilience terms of the consequence factor and a very low bin in the scoring of exposure terms in ERAF risk equation were added;
3. the intensity term in exposure was divided into amount and frequency components, and exposure was calculated as the product of the geometric mean of area, depth and temporal overlaps and the geometric mean of intensity;
4. POTENCY of stressors was estimated as the sum of risk from a stressor across all SECs with which it interacts; and
5. scoring decisions were reviewed by subject matter experts (SMEs) prior to the estimation of risk scores.
• Eleven SECs were identified in the EHV MPA (six species SECs, four habitat SECs, and one community SEC) during the scoping phase. Sixteen SECs were identified in the SKB MPA, but only fourteen (ten species and four habitat SECs) underwent a Level 2 Risk Assessment. The selection of SECs for both risk assessments was confined to components that could be managed at the MPA scale, which excluded species groups such as zooplankton and transient species, such as marine mammals and sea birds.
• Pathways of effects (POE) models were developed and used to identify stressors associated with human activities at a scale specific to each stressor. For example, substrate disturbance was divided into both crushing and resuspended sediment stressors. The extensive justifications of the POE models, combined with the strength-of-evidence interaction matrices used in the EHV and SKB MPA applications, are considered a suitable approach for proceeding in absence of CSAS peer-review of the POE models.
• Stressors from human activities in each MPA were categorized into potential and current snapshot based on frequency of occurrence and knowledge of exposure. Current snapshot stressors are from activities occurring predictably at frequencies of less than one year (e.g., daily, monthly, every few weeks), and for which there is some knowledge of exposure, whereas potential stressors are from activities that are unpredictable, but have intervals greater than one year, and were scored assuming a worst-case scenario for exposure and consequence.
• Three species SECs (Ridgeia piscesae – high flux and R. piscesae – low flux) and Paralvinella sulfincola, as well as the benthic clam bed community SEC, had the highest cumulative risk scores in the EHV MPA, while the four habitat SECs that were assessed (diffuse basalt flows, inactive chimneys, active venting chimneys, hydrothermal plume) had the lowest cumulative risk scores. The stressors with the highest POTENCY scores were debris, substrate disturbance (crushing) during sampling, substrate disturbance (crushing) during submersible operations, and aquatic invasive species from submersible operations.
• The highest cumulative risk scores in the SKB MPA were estimated for the Bamboo Coral Isidella, Alcyonacea coral habitat, and sponge habitat SECs. Rougheye Rockfish had the highest cumulative risk score of all fish SECs, but there was considerable overlap among fish SECs. The stressors with the highest potency were oil spills, seismic testing and aquatic invasive species (AIS). Each of these stressors was categorized as potential stressors.
• The highest SEC risk scores in both MPAs are driven by high levels of uncertainty in the exposure and/or consequence terms of the risk equation. Whether this uncertainty is related to a lack of data or lack of knowledge of SEC exposure or consequences was not assessed.
• All potential stressors (oil spills, AIS, debris, sound generation from seismic testing) had among the highest potency scores in each MPA. These scores tend to be driven by high uncertainty, particularly for Exposure terms in the risk equation, because they are scored on a worst-case scenario basis. Better monitoring will assist with quantification of exposure of SECs and improved understanding of the risks associated with these stressors within each MPA area.
• The SEC lists and analysis of stressors and drivers of that risk are suitable to inform the development of risk-based indicators in EHV and SKB MPAs.
• The review of scoring decisions by SMEs is a quality assurance procedure whose primary impact was a reduction in the uncertainty associated with some of the scoring decisions.  Using SMEs to review scoring decisions prior to estimating risk scores is recommended for future applications of the ERAF.
• The modifications to the ERAF described in the EHV and SKP MPA Level 2 risk assessment applications improved contrast among SECs based on estimated cumulative risk scores and provide additional information on stressors (potential and current snapshot) and the drivers of risk to SECs. These operational modifications are recommended for future applications of the ERAF.
• Scoring the risk to ecosystem/community property SECs was challenging because the recovery factors described in DFO (2012) are relative and require baseline data, which is limited in both MPAs. Future Level 2 applications of the ERAF will benefit from baseline data collection through ongoing monitoring in each MPA.
• The ERAF is an iterative process that can be updated as new information becomes available through monitoring or research or as a result of new activity proposals. It is recommended that work be conducted to identify triggers for updates to the ERAF assessments of an area. 
• It is recommended that additional considerations be added to the SEC selection process into order to overcome the challenge of capturing the extreme species endemism in the EHV MPA.
• It is recommended that SEC exposure to potential stressors (noise from vessels, sound generation from air guns used for seismic testing), and fishing be quantified at each MPA, so that the risks from each of these stressors can be better understood.

This Science Advisory Report is from the February 11-13, 2014 and March 13, 2015 Application of an Ecological Risk Assessment Framework to Inform Ecosystem-based Management for SGaan Kinghlas-Bowie Seamount and Endeavour Hydrothermal Vents Marine Protected Areas. Additional publications from this meeting will be posted on the Fisheries and Oceans Canada (DFO) Science Advisory Schedule as they become available.

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