northern quahog and soft-shell clam - the safina...

AND

Northern quahog and soft-shell clamNorthern quahog and soft-shell clamMercenaria mercenaria, Mya arenaria

CanadaCanada

Rakes and ShovelsRakes and Shovels

October 3, 2016

The Sa na Center Seafood Analysts

Fisheries Standard Version V2

Disclaimer: Seafood Watch and The Sa na Center strive to ensure that all our Seafood Reports and recommendations contained therein are accurate and re ect the most up-to-date evidence available at the time of publication. All our reports are peer-reviewed for accuracy and completeness by external scientists with expertise in ecology, sheries science or aquaculture.Scienti c review, however, does not constitute an endorsement of the Seafood Watch program or of The Sa na Center or their recommendations on the part of the reviewingscientists.Seafood Watch and The Sa na Center are solely responsible for the conclusions reached in this report. We always welcome additional or updated data that can be used for the next revision. Seafood Watch and Seafood Reports are made possible through a grant from the David and Lucile Packard Foundation and other funders.

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Table of Contents

About The Safina Center

About Seafood Watch

Guiding Principles

Summary

Final Seafood Recommendations

Introduction

Assessment

Criterion 1: Impacts on the species under assessment

Criterion 2: Impacts on other species

Criterion 3: Management Effectiveness

Criterion 4: Impacts on the habitat and ecosystem

Acknowledgements

References

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About The Sa na CenterAbout The Sa na Center

The Sa na Center (formerly Blue Ocean Institute) translates scienti c information into languagepeople can understand and serves as a unique voice of hope, guidance, and encouragement.The Sa na Center (TSC) works through science, art, and literature to inspire solutions and adeeper connection with nature, especially the sea. Our mission is to inspire more people toactively engage as well-informed and highly motivated constituents for conservation.

Led by conservation pioneer and MacArthur fellow, Dr. Carl Sa na, we show how nature,community, the economy and prospects for peace are all intertwined. Through Sa na’s books,essays, public speaking, PBS television series, our Fellows program and Sustainable Seafoodprogram, we seek to inspire people to make better choices.

The Sa na Center was founded in 2003 by Dr. Carl Sa na and was built on three decades ofresearch, writing and policy work by Dr. Sa na.

The Sa na Center’s Sustainable Seafood Program The Center ’s founders created the rst seafood guide in 1998. Our online seafood guide nowencompasses over 160-wild-caught species. All peer-reviewed seafood reports are transparent,authoritative, easy to understand and use. Seafood ratings and full reports are available on ourwebsite under Seafood choices. tsc’s sustainable seafood program helps consumers, retailers,chefs and health professionals discover the connection between human health, a healthyocean, shing and sustainable seafood.

Our online guide to sustainable seafood is based on scienti c ratings for more than 160wild-caught seafood species and provides simple guidelines. Through our expandedpartnership with the Monterey Bay Aquarium, our guide now includes seafood ratings fromboth The Sa na Center and the Seafood Watch® program.We partner with Whole Foods Market (WFM) to help educate their seafood suppliers andsta , and provide our scienti c seafood ratings for WFM stores in the US and UK.Through our partnership with Chefs Collaborative, we created Green Chefs/Blue Ocean, afree, interactive, online sustainable seafood course for chefs and culinary professionals.Our website features tutorials, videos, blogs, links and discussions of the key issues such asmercury in seafood, bycatch, over shing, etc.

Check out our Fellows Program, learn more about our Sustainable Seafood Program and CarlSa na’s current work at www.sa nacenter.org .

The Sa na Center is a 501 (c) (3) nonpro t organization based in the School of Marine &Atmospheric Sciences at Stony Brook University, Long Island, NY. www.sa nacenter.orgadmin@sa nacenter.org | 631.632.3763

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http://www.safinacenter.org/seafoods

http://safinacenter.org/programs/sustainable-seafood-program/green-chefsblue-ocean-online-course/

http://livepage.apple.com/

http://www.safinacenter.org

http://www.safinacenter.org

mailto:[email protected]

About Seafood WatchAbout Seafood Watch

Monterey Bay Aquarium’s Seafood Watch® program evaluates the ecological sustainability ofwild-caught and farmed seafood commonly found in the United States marketplace. SeafoodWatch® de nes sustainable seafood as originating from sources, whether wild-caught orfarmed, which can maintain or increase production in the long-term without jeopardizing thestructure or function of a ected ecosystems. Seafood Watch® makes its science-basedrecommendations available to the public in the form of regional pocket guides that can bedownloaded from www.seafoodwatch.org. The program’s goals are to raise awareness ofimportant ocean conservation issues and empower seafood consumers and businesses tomake choices for healthy oceans.

Each sustainability recommendation on the regional pocket guides is supported by a SeafoodReport. Each report synthesizes and analyzes the most current ecological, sheries andecosystem science on a species, then evaluates this information against the program’sconservation ethic to arrive at a recommendation of “Best Choices,” “Good Alternatives” or“Avoid.” The detailed evaluation methodology is available upon request. In producing theSeafood Reports, Seafood Watch® seeks out research published in academic, peer-reviewedjournals whenever possible. Other sources of information include government technicalpublications, shery management plans and supporting documents, and other scienti creviews of ecological sustainability. Seafood Watch® Research Analysts also communicateregularly with ecologists, sheries and aquaculture scientists, and members of industry andconservation organizations when evaluating sheries and aquaculture practices. Capture

sheries and aquaculture practices are highly dynamic; as the scienti c information on eachspecies changes, Seafood Watch®’s sustainability recommendations and the underlyingSeafood Reports will be updated to re ect these changes.

Parties interested in capture sheries, aquaculture practices and the sustainability of oceanecosystems are welcome to use Seafood Reports in any way they nd useful. For moreinformation about Seafood Watch® and Seafood Reports, please contact the Seafood Watch®program at Monterey Bay Aquarium by calling 1-877-229-9990.

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Guiding PrinciplesGuiding Principles

The Sa na Center and Seafood Watch de ne sustainable seafood as originating from sources,whether shed or farmed, that can maintain or increase production in the long-term withoutjeopardizing the structure or function of a ected ecosystems.

Based on this principle, Seafood Watch and the Sa na Center have developed foursustainability criteria for evaluating wild-catch sheries for consumers and businesses. Thesecriteria are:

How does shing a ect the species under assessment?How does the shing a ect other, target and non-target species?How e ective is the shery’s management?How does the shing a ect habitats and the stability of the ecosystem?

Each criterion includes:

Factors to evaluate and scoreGuidelines for integrating these factors to produce a numerical score and rating

Once a rating has been assigned to each criterion, we develop an overall recommendation.Criteria ratings and the overall recommendation are color-coded to correspond to thecategories on the Seafood Watch pocket guide and the Sa na Center ’s online guide:

Best Choice/Green: Are well managed and caught in ways that cause little harm to habitats orother wildlife.

Good Alternative/Yellow: Buy, but be aware there are concerns with how they’re caught.

Avoid/Red Take a pass on these for now. These items are over shed or caught in ways thatharm other marine life or the environment.

“Fish” is used throughout this document to refer to n sh, shell sh and other invertebrates

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SummarySummary

This reports assesses the sustainability of the northern quahog or hard clam (Mercenariamercenaria) and soft-shell clam (Mya arenaria) caught in Canadian Atlantic waters with rakes,shovels, or picks. The ratings in this assessment cover virtually all landings of northern quahogand softshell clams in Canada. All sheries are rated "Green/Best Choice."

The northern quahog is found in the Western Atlantic from the Southern Gulf of St. Lawrenceto Florida, as well as in the Gulf of Mexico as far south as the Yucatan Peninsula. It begins lifeas male and changes to female as it grows, typically living for around 8 years. Soft-shell clamhas a worldwide distribution. Along the North American Atlantic Coast, it ranges fromLabrador to North Carolina. Soft-shell clam may live for 10–12 years and grow to more than 11cm.

In Canada, the hard clam is commercially shed in the Southern Gulf of St. Lawrence (GulfManagement Region), and the soft-shell clam is shed in the Gulf, Maritimes, and Quebecregions. The abundance of the hard clam and the soft-shell clam is uncertain in all regions, butseveral management regulations are in place, such as minimum size limits and closed shingseasons. The sheries are managed by the Department of Fisheries and Oceans Canada (DFO).

Fishers use hand-held tools including rakes, shovels, and picks to capture clams. These shinggears result in minimal bycatch, but cause low damage to bottom habitats.

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Final Seafood RecommendationsFinal Seafood Recommendations

Scoring GuideScoring Guide

Scores range from zero to ve where zero indicates very poor performance and ve indicatesthe shing operations have no signi cant impact.

Final Score = geometric mean of the four Scores (Criterion 1, Criterion 2, Criterion 3, Criterion 4).

Best Choice/Green = Final Score >3.2, and no Red Criteria, and no Critical scoresGood Alternative/Yellow = Final score >2.2-3.2, and neither Harvest Strategy (Factor 3.1) norBycatch Management Strategy (Factor 3.2) are Very High Concern2, and no more than oneRed Criterion, and no Critical scoresAvoid/Red = Final Score ≤2.2, or either Harvest Strategy (Factor 3.1) or Bycatch ManagementStrategy (Factor 3.2) is Very High Concern or two or more Red Criteria, or one or more Criticalscores.

Because e ective management is an essential component of sustainable sheries, Seafood Watch issuesan Avoid recommendation for any shery scored as a Very High Concern for either factor underManagement (Criterion 3).

SPECIES/FISHERY

CRITERION 1:IMPACTS ONTHE SPECIES

CRITERION 2:IMPACTS ONOTHERSPECIES

CRITERION 3:MANAGEMENTEFFECTIVENESS

CRITERION 4:HABITAT ANDECOSYSTEM

OVERALLRECOMMENDATION

Northern quahogCanada SouthernGulf of St.Lawrence, Rakes(wild)

Yellow (2.644) Green (5.000) Yellow (3.000) Yellow (3.122) Best Choice (3.335)

Softshell clamMaritimes NorthAtlantic, Rakes(wild)


Softshell clamQuebec NorthAtlantic, Rakes(wild)


Softshell clamGulf Mgmt. regionNorth Atlantic,Rakes (wild)


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IntroductionIntroduction

Scope of the analysis and ensuing recommendationScope of the analysis and ensuing recommendation

This reports assesses the sustainability of the northern quahog or hard clam (Mercenariamercenaria) and soft-shell clam (Mya arenaria) sheries in Canadian Atlantic waters. The hardclam is commercially shed in the Southern Gulf of St. Lawrence (Gulf Management Region),while the soft-shell clam is shed in the Gulf, Maritimes, and Quebec Management Regions.The ratings in this assessment cover virtually all landings of northern quahog and softshellclams in Canada. Fishers use hand-held tools including rakes, shovels, and picks to captureclams.

Species OverviewSpecies Overview

The northern quahog is found in the Western Atlantic from the Southern Gulf of St. Lawrenceto Florida, as well as in the Gulf of Mexico as far south as the Yucatan Peninsula (Eversole 1987)(DFO 2001). It primarily lives in estuaries or sheltered bays, and is found to a depth of 15meters (m) on sandy, silty, and mud bottoms. It buries itself 5–10 cm below the sedimentsurface. Its distribution often overlaps with the eastern/American oyster. The hard clam has athick white shell, with a shiny purple color on the edge of the anterior end (DFO 1996a) (DFO1996e) (DFO 2001). It begins life as male and changes to female as it grows, typically living foraround 8 years (Hill 2004).

Soft-shell clam (Mya arenaria) has a worldwide distribution. Along the North American AtlanticCoast, it ranges from Labrador to North Carolina (DFO 2001) (DFO 2011). It lives in estuaries andsheltered bays on mud and clay bottoms, and buries itself 20–35 cm below the sedimentsurface. The soft-shell clam has a long, thin, brittle white shell (DFO 2001) (DFO 2011). Soft-shellclam may live for 10–12 years and grow to more than 11 cm (Abraham andDillon1986) (Maximovich and Guerassimova 2003) (DFO 2011).

In Canada, the hard clam is commercially shed in the Southern Gulf of St. Lawrence (GulfManagement Region), while the soft-shell clam is shed in the Gulf, Maritimes, and Quebecregions (see map below). The sheries are managed by the Department of Fisheries andOceans Canada (DFO).

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Figure 1 Map of the Department of Fisheries and Oceans Canada (DFO) Management Regions.Image from DFO.

Production StatisticsProduction Statistics

Gulf Region

Commercial clam catches have been declining in the Gulf Region over the lastdecade. Hard clam catches peaked at around 1,000 metric tons (MT) in the early1990s and early 2000s, but have since greatly declined, averaging only 310 MT inrecent years (2010–2014). Soft-shell clam catches also peaked at over 1,000 MT inthe early 2000s and have been declining since, averaging 490 MT in recentyears. In 2014, catches of both the hard clam (116 MT) and soft-shell clam (221 MT) were the

lowest on record (pers. comm., DFO Gulf Region, Statistics Division 2016). Total commercialclam catches (all species) in this region ranged from 1,300 to 1,500 MT from 2010to 2013, and were only 656 MT in 2014 (DFO 2016d).

Maritimes Region

Commercial catches of the soft-shell clam in the Maritimes Region have uctuated over theyears. Catches peaked at 2,000 MT in the early 2000s, declined to less than 500 MT in the late2000s, and have increased again in recent years, with catches hovering around 1,200 MT from

2011–2014 (pers. comm., DFO Maritimes Region 2016). Total commercial clam catches (allspecies) in the Maritimes have ranged from 1,500 to 2,400 MT from 2011 to 2014 (DFO 2016d).

Quebec RegionIn Quebec, commercial catches of soft-shell clam peaked at 1,173 MT in 2000 and have since

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declined to less than 100 MT (DFO 2011). Annual catches from 2012–2015 averaged only 34MT (pers. comm., DFO Quebec Region 2016). Total commercial clam catches (all species) inQuebec over this period (2012–2014) have ranged from 1,000 to 1,300 MT (DFO 2016d).

Importance to the US/North American market.Importance to the US/North American market.

Available import/export statistics for “clam” generally do not provide a species-level breakdownof data. Therefore, the following data are for all clams and not speci c to the sheries in thisreport. In 2015, the U.S. imported a total of 10,264 MT of prepared/preserved clams, 8,270 MTof boiled canned clams, 3,063 MT of live/fresh clams, and 1,762 MT offrozen/dried/salted/brined clams. The largest imports were from China (10,855 MT), followed byCanada (3,387 MT), Vietnam (2,050 MT), and Indonesia (840 MT) (NMFS 2016). Total reportedCanadian clam exports in 2015 were 7,871 MT with a value of CAD 90 million (DFO 2016e).

Common and market names.Common and market names.

Other common and market names for the hard clam include bay quahog, northern quahog,cherrystone, and littleneck. Other common and market names for the soft-shell clam includesteamer or maninose clam.

Primary product formsPrimary product forms

Hard clam/northern quahog is often served raw on the half shell (littlenecks), baked, or used indishes such as clam chowder or clam sauces (cherrystone and chowder clams). Soft-shell clamsare commonly served steamed or fried.

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AssessmentAssessment

This section assesses the sustainability of the shery(s) relative to the Seafood Watch Criteriafor Fisheries, available at http://www.seafoodwatch.org.

Criterion 1: Impacts on the species under assessmentCriterion 1: Impacts on the species under assessment

This criterion evaluates the impact of shing mortality on the species, given its current abundance.The inherent vulnerability to shing rating in uences how abundance is scored, when abundance isunknown.

The nal Criterion 1 score is determined by taking the geometric mean of the abundance and shingmortality scores. The Criterion 1 rating is determined as follows:

Score >3.2=Green or Low ConcernScore >2.2 and ≤3.2=Yellow or Moderate ConcernScore ≤2.2=Red or High Concern

Rating is Critical if Factor 1.3 (Fishing Mortality) is Critical

Criterion 1 SummaryCriterion 1 Summary

In Canada, the hard clam is commercially shed in the Southern Gulf of St.Lawrence (Gulf Management Region), while the soft-shell clam is shed in the Gulf,Maritimes, and Quebec regions. Abundance and shing mortality relative tosustainable levels are unknown in all regions; however, these clam species are not

NORTHERN QUAHOG

Region / MethodInherentVulnerability Abundance Fishing Mortality Score

Canada/Southern Gulf of St.Lawrence Rakes (wild)

Low 3.00: ModerateConcern

2.33: ModerateConcern

Yellow(2.644)

SOFTSHELL CLAM

Region / MethodInherentVulnerability Abundance Fishing Mortality Score

Maritimes/North Atlantic Rakes(wild)

Medium 3.00: ModerateConcern


Yellow(2.644)

Quebec/North Atlantic Rakes(wild)



Yellow(2.644)

Gulf Mgmt. region/North AtlanticRakes (wild)



Yellow(2.644)

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considered highly vulnerable to shing. Overall, there is moderate concern for theimpacts of the sheries on the hard clam and soft-shell clam populations.

Criterion 1 AssessmentCriterion 1 Assessment

SCORING GUIDELINES

Factor 1.1 - Inherent VulnerabilityFactor 1.1 - Inherent Vulnerability

Low—The FishBase vulnerability score for species is 0-35, OR species exhibits life historycharacteristics that make it resilient to shing, (e.g., early maturing).Medium—The FishBase vulnerability score for species is 36-55, OR species exhibits life historycharacteristics that make it neither particularly vulnerable nor resilient to shing, (e.g., moderateage at sexual maturity (5-15 years), moderate maximum age (10-25 years), moderate maximumsize, and middle of food chain).High—The FishBase vulnerability score for species is 56-100, OR species exhibits life historycharacteristics that make is particularly vulnerable to shing, (e.g., long-lived (>25 years), latematuring (>15 years), low reproduction rate, large body size, and top-predator). Note: The FishBasevulnerability scores is an index of the inherent vulnerability of marine shes to shing based on lifehistory parameters: maximum length, age at rst maturity, longevity, growth rate, naturalmortality rate, fecundity, spatial behaviors (e.g., schooling, aggregating for breeding, or consistentlyreturning to the same sites for feeding or reproduction) and geographic range.

Factor 1.2 - AbundanceFactor 1.2 - Abundance

5 (Very Low Concern)—Strong evidence exists that the population is above target abundance level(e.g., biomass at maximum sustainable yield, BMSY) or near virgin biomass.4 (Low Concern)—Population may be below target abundance level, but it is considered notover shed3 (Moderate Concern) —Abundance level is unknown and the species has a low or mediuminherent vulnerability to shing.2 (High Concern)—Population is over shed, depleted, or a species of concern, OR abundance isunknown and the species has a high inherent vulnerability to shing.1 (Very High Concern)—Population is listed as threatened or endangered.

Factor 1.3 - Fishing MortalityFactor 1.3 - Fishing Mortality

5 (Very Low Concern)—Highly likely that shing mortality is below a sustainable level (e.g., belowshing mortality at maximum sustainable yield, FMSY), OR shery does not target species and its

contribution to the mortality of species is negligible (≤ 5% of a sustainable level of shingmortality).3.67 (Low Concern)—Probable (>50%) chance that shing mortality is at or below a sustainablelevel, but some uncertainty exists, OR shery does not target species and does not adversely a ectspecies, but its contribution to mortality is not negligible, OR shing mortality is unknown, but thepopulation is healthy and the species has a low susceptibility to the shery (low chance of beingcaught).2.33 (Moderate Concern)—Fishing mortality is uctuating around sustainable levels, OR shing

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mortality is unknown and species has a moderate-high susceptibility to the shery and, if species isdepleted, reasonable management is in place.1 (High Concern)—Over shing is occurring, but management is in place to curtail over shing, OR

shing mortality is unknown, species is depleted, and no management is in place.0 (Critical)—Over shing is known to be occurring and no reasonable management is in place tocurtail over shing.

NORTHERN QUAHOG


CANADA/SOUTHERN GULF OF ST. LAWRENCE, RAKES (WILD)

Low

Inherent vulnerability for hard clam (M. mercenaria) is assessed as "low."

On average, hard clam lives to a maximum of 8 years, but evidence suggests that, if it is notsubjected to predation or commercial exploitation, it may live as long as 40 years (Hill 2004).Hard clam reaches reproductive maturity at a size of 33 mm (DFO 2001) and between 1 and 2years of age. Clams that live in warmer, southern climates grow faster and reach reproductivematurity sooner than clams that live in cooler, northern climates (Hill 2004). Hard clam is aprotandrous sequential hermaphrodite, with most individuals rst achieving reproductivematurity as males. About half the individuals eventually metamorphose into females as theygrow. This complicates management because the sex distribution changes with the agedistribution (DFO 2001). Hard clam is a broadcast spawner (Hadley and Coen 2005). Growthand survival are density-dependent, and depensatory dynamics (Allee e ect) at lowpopulation sizes are likely (Eversole 1987).

Rationale:

Table 1: Results from Seafood Watch sh vulnerability rubric (SFW criteria document, p. 4).Attribute scores can range from 1–3, with higher scores signifying more resilient life historyattributes.

Vulnerability attribute Category Score

Average age at maturity < 5 years 3

Average maximum age < 10 years 3

Fecundity > 100 eggs N/A

Reproductive strategy Broadcast spawner 3

Density dependence

Depensatory dynamics(Allee e ect)demonstrated or likelyat low population sizes

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Species with average attribute scores between 2.46 and 3.00 are deemed to have a"low" vulnerability.

Average Score Low Vulnerability 2.5


Moderate Concern

There has been no formal population assessment of the hard clam in the Southern Gulf of St.Lawrence, so abundance relative to target abundance goals is unknown. Declines in hardclam densities and landings were reported in the 1990s (DFO 1996a) (Landry et al. 2001) (DFO2001). Recent abundance information is not available. Because abundance is unknown andhard clam has a low vulnerability to shing, we have awarded a "moderate" concern score.


Moderate Concern

There has been no formal assessment of the hard clam population, so shing mortality isunknown. Commercial catches of hard clam have declined considerably since the 1990s/early2000s. From 1990 to 2005, hard clam catches averaged 850 MT (DFO 1996a) (pers. comm., DFOGulf Region, Statistics Division 2016). Since then, catches have generally been less than 500MT. In 2014, reported hard clam catches in the Gulf Region were only 116 MT, and preliminarycatches for 2015 are 124 MT. The number of licensed shers in the shery has also declined(pers. comm., DFO Gulf Region, Statistics Division 2016). Because of the limited information, a"moderate" concern score is awarded.

Rationale:

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SOFTSHELL CLAM


Figure 2 Commercial landings of the hard clam in the Southern Gulf of St. Lawrence (GulfManagement Region) from 1990–2015. Data from DFO 1996a and DFO Gulf Region, StatisticsDivision.

MARITIMES/NORTH ATLANTIC, RAKES (WILD)QUEBEC/NORTH ATLANTIC, RAKES (WILD)GULF MGMT. REGION/NORTH ATLANTIC, RAKES (WILD)

Medium

Inherent vulnerability for the soft-shell clam (Mya arenaria) is assessed as medium.

Soft-shell clam reaches reproductive maturity within 5 years, at a size of 35–40 mm (Abrahamand Dillon 1986) (Beal et al. 1999) (DFO 2001). The average lifespan is 10–12 years, thoughthere is some indication that it could live up to 28 years (Abraham and Dillon 1986). Soft-shellclam reproduces through broadcast spawning and is density-dependent, with depensatorydynamics (Allee e ect) likely when populations are small (Gascoigne and Lipcius 2004) (Seitzet al. 2001).

Rationale:

Table 2: Results from Seafood Watch sh vulnerability rubric (SFW criteria document, p. 4).Attribute scores can range from 1–3, with higher scores signifying more resilient life historyattributes.

16


Species with average attribute scores between 1.85 and 2.45 are deemed to have a "medium"vulnerability.

Vulnerability attribute Category Score

Average age at maturity < 5 years 3

Average maximum age 10–25 years 2

Fecundity > 100 eggs N/A

Reproductive strategy Broadcast spawner 3

Density dependence

Depensatory dynamics(Allee e ect)demonstrated or likelyat low population sizes

1

Average Score Medium Vulnerability 2.25

MARITIMES/NORTH ATLANTIC, RAKES (WILD)

Moderate Concern

There has been no formal assessment of the soft-shell clam in the Canadian MaritimesRegion, so abundance relative to target abundance goals is unknown. The last status reportsfor the soft-shell clam resource in the Maritimes were in 1996 (DFO 1996d) (DFO 1996c).Because abundance is unknown and this species has a medium vulnerability to shing, a"moderate" concern score is awarded.

QUEBEC/NORTH ATLANTIC, RAKES (WILD)

Moderate Concern

Commercial shing for soft-shell clam in the Quebec Region primarily takes place on theUpper North Shore. Commercial catches peaked in 2000 but have since been declining. Catchrates on most clam beds in the Upper North Shore were lower from 2006–2009 compared to2002–2005, but have increased since 2009 in most areas. In the Reserve Pessamit Sud area,the density of legal and sub-legal sized clams was estimated to have declined by 35% and57%, respectively, between 2005 and 2010 (DFO 2011). Because of the variable abundancetrends, the lack of de ned target abundance goals, and this species' medium vulnerability to

shing, we have awarded a "moderate" concern score.

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There has been no formal assessment of the soft-shell clam in the Canadian Gulf Region, soabundance relative to target abundance goals is unknown. Declines in catches, particularly inEastern New Brunswick, were observed in the 1990s and 2000s, prompting concern over thehealth of the population. In 2006, scientists evaluated the status of the soft-shell clamresource in three areas of Eastern New Brunswick (Richibucto region, Tabusintac watershed,and Heron Island) by interviewing shers, managers, and conservationists. The consensuswas that the abundance of soft-shell clam is very low in the Richibucto region, stable in theTabusintac watershed, and recovering in Heron Island (Hicks and Ouellette 2011). Furtherabundance information is not available for this region. Because of the limited informationand this species' medium vulnerability to shing, a "moderate" concern score is awarded.

MARITIMES/NORTH ATLANTIC, RAKES (WILD)

Moderate Concern

There is no recent information on the status of the soft-shell clam resource in the MaritimesRegion. Commercial catches have uctuated over the years (see gure below) and haveaveraged 1,200 MT from 2011–2015 (pers. comm., DFO Maritimes Region 2016). Because

shing mortality relative to a sustainable level is unknown, a "moderate" concern score isawarded.

Rationale:

Figure 3 Commercial landings of the soft-shell clam in the Maritimes Management Regionfrom 1996–2015. Data from DFO Maritimes Region.

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GULF MGMT. REGION/NORTH ATLANTIC, RAKES (WILD)

Moderate Concern

QUEBEC/NORTH ATLANTIC, RAKES (WILD)

Moderate Concern

Commercial catches of soft-shell clam in Quebec peaked at 1,200 MT in 2000 but have sincedeclined to less than 100 MT (see gure below). The number of shers participating in the

shery and shing e ort have also declined. Commercial shing levels are believed to berelatively low, but recreational shing levels are unknown. Undersized clams often exceed15% of the catch in many areas, which is concerning (DFO 2011). Because shing mortalityrelative to a sustainable level is unknown, a "moderate" concern score is awarded.

Rationale:

Figure 4 Commercial landings of the soft-shell clam in Quebec. Figure from DFO 2011.

GULF MGMT. REGION/NORTH ATLANTIC, RAKES (WILD)

Moderate Concern

There has been no formal assessment of the soft-shell clam in the Gulf Management region,so shing mortality is unknown. But previous reports have suggested that over shing mayhave occurred in the past (DFO 1996b) (DFO 2001) (Hicks and Ouellette 2011). In the Gulf, soft-shell clams are shed o the coasts of both Eastern New Brunswick and Prince Edward Island,but catches have historically been greater in Eastern New Brunswick (DFO 1996b). The soft-shell clam has historically been the most important commercially exploited clam species inEastern New Brunswick, but catches have declined over time ((Hicks and Ouellette 2011), see

gures below). Total soft-shell clam catches for the Gulf Region averaged 860 MT during the1990s, 785 MT from 2000–2009, and 450 MT since 2010. The number of licensed shers in the

shery has also declined. In 2014, soft-shell clam catches in the Gulf region were 221 MT, andpreliminary catches for 2015 are 221 MT (pers. comm., DFO Gulf Region, Statistics Division2016). Recreational catches are not reported and there is likely underreporting of commercialcatches (Hicks and Ouellette 2011). Because of the limited information, we have awarded ascore of "moderate" concern.

19

Rationale:

Figure 5 Commercial landings of the soft-shell clam in the Gulf Management Region from1990–2015. Data from DFO 1996b and DFO Gulf Region, Statistics Division.

Figure 6 Commercial landings and value of the soft-shell clam in Eastern New Brunswick from1984–2007. Figure from Hicks and Ouellette 2011.

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Criterion 2: Impacts on other speciesCriterion 2: Impacts on other species

All main retained and bycatch species in the shery are evaluated in the same way as the speciesunder assessment were evaluated in Criterion 1. Seafood Watch® de nes bycatch as all sheries-related mortality or injury to species other than the retained catch. Examples include discards,endangered or threatened species catch, and ghost shing.

To determine the nal Criterion 2 score, the score for the lowest scoring retained/bycatch species ismultiplied by the discard rate score (ranges from 0-1), which evaluates the amount of non-retainedcatch (discards) and bait use relative to the retained catch. The Criterion 2 rating is determined asfollows:


Rating is Critical if Factor 2.3 (Fishing Mortality) is Crtitical

Criterion 2 Summary

NORTHERN QUAHOG - CANADA/SOUTHERN GULF OF ST. LAWRENCE - RAKES (WILD)

Subscore: 5.000 Discard Rate: 1.00 Score: 5.000

SpeciesInherentVulnerability Abundance Fishing Mortality Subscore

No other main species caught

SOFTSHELL CLAM - GULF MGMT. REGION/NORTH ATLANTIC - RAKES (WILD)

Subscore: 5.000 Discard Rate: 1.00 5.000



SOFTSHELL CLAM - MARITIMES/NORTH ATLANTIC - RAKES (WILD)




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Score:

Score:

Fishers use hand tools such as rakes, shovels, and picks to capture clams in shallow waters andmud ats. Surface marks on the substrate can help shers identify areas where clams arepresent, allowing them to target those areas and avoid damaging areas without clams {Brownand Wilson 1997}. As sediment is raked or dug, infaunal organisms are brought to the surface,but the shers can easily identify and take the target species, while leaving behind nontargetspecies and undersized target species {Barnette 2001}.

Although no bycatch is taken, concern has been raised that hard clam sheries may impactoyster reefs because hard clam and oyster habitats often overlap {DFO 1996a} {Lenihan andMicheli 2000}. In the Southern Gulf of Saint Lawrence, oysters and clams are harvestedconcurrently but by di erent shers {DFO 1996a}. Researchers and shers have reported thatclam raking can damage oysters by cracking their shells or burying them, but a study byLenihan and Micheli found that harvesting clams alone does not reduce oyster density morethan harvesting both species concurrently {Lenihan and Micheli 2000}. Because raking forclams in areas where oysters are already targeted does not have a signi cant impact on oysterpopulations, and because no bycatch is taken, this shery receives a score of 5.

2.4 - Discards + Bait / Landings2.4 - Discards + Bait / Landings

SOFTSHELL CLAM - QUEBEC/NORTH ATLANTIC - RAKES (WILD)




CANADA / SOUTHERN GULF OF ST. LAWRENCE, RAKES (WILD)MARITIMES / NORTH ATLANTIC, RAKES (WILD)QUEBEC / NORTH ATLANTIC, RAKES (WILD)GULF MGMT. REGION / NORTH ATLANTIC, RAKES (WILD)

< 20%

Fishers use hand tools such as rakes, shovels, and picks to capture clams in shallow watersand mud ats. These shing methods allow shers to be highly selective about their catch andto return unwanted species to the water alive. Because bycatch and dead discards areminimal, we have awarded the lowest score.

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Score:

Criterion 3: Management EffectivenessManagement is separated into management of retained species (harvest strategy) and management of

non-retained species (bycatch strategy).

The nal score for this criterion is the geometric mean of the two scores. The Criterion 3 rating isdetermined as follows:

Score >3.2=Green or Low ConcernScore >2.2 and ≤3.2=Yellow or Moderate ConcernScore ≤2.2 or either the Harvest Strategy (Factor 3.1) or Bycatch Management Strategy (Factor 3.2)is Very High Concern = Red or High Concern

Rating is Critical if either or both of Harvest Strategy (Factor 3.1) and Bycatch Management Strategy(Factor 3.2) ratings are Critical.



SCORING GUIDELINES

Factor 3.1: Harvest StrategyFactor 3.1: Harvest Strategy

Seven subfactors are evaluated: Management Strategy, Recovery of Species of Concern, Scienti cResearch/Monitoring, Following of Scienti c Advice, Enforcement of Regulations, Management TrackRecord, and Inclusion of Stakeholders. Each is rated as ‘ine ective,’ ‘moderately e ective,’ or ‘highlye ective.’

5 (Very Low Concern)—Rated as ‘highly e ective’ for all seven subfactors considered4 (Low Concern)—Management Strategy and Recovery of Species of Concern rated ‘highlye ective’ and all other subfactors rated at least ‘moderately e ective.’3 (Moderate Concern)—All subfactors rated at least ‘moderately e ective.’2 (High Concern)—At minimum, meets standards for ‘moderately e ective’ for ManagementStrategy and Recovery of Species of Concern, but at least one other subfactor rated‘ine ective.’1 (Very High Concern)—Management exists, but Management Strategy and/or Recovery ofSpecies of Concern rated ‘ine ective.’

Region / MethodHarvestStrategy

BycatchStrategy Score

Canada / Southern Gulf of St. Lawrence / Rakes(wild)

3.000: Moderate Concern

All retained Yellow (3.000)

Gulf Mgmt. region / North Atlantic / Rakes (wild) Yellow (3.000)

Maritimes / North Atlantic / Rakes (wild) Yellow (3.000)

Quebec / North Atlantic / Rakes (wild) Yellow (3.000)

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All retained


All retained


All retained

0 (Critical)—No management exists when there is a clear need for management (i.e., sherycatches threatened, endangered, or high concern species), OR there is a high level of Illegal,unregulated, and unreported shing occurring.

Factor 3.1 SummaryFactor 3.1 Summary

Subfactor 3.1.1 – Management Strategy and ImplementationSubfactor 3.1.1 – Management Strategy and Implementation

Considerations: What type of management measures are in place? Are there appropriatemanagement goals, and is there evidence that management goals are being met? To achieve a highlye ective rating, there must be appropriate management goals, and evidence that the measures inplace have been successful at maintaining/rebuilding species.

FACTOR 3.1: MANAGEMENT OF FISHING IMPACTS ON RETAINED SPECIES

Region /Method Strategy Recovery Research Advice Enforce Track Inclusion

Canada /Southern Gulfof St.Lawrence /Rakes (wild)

ModeratelyE ective

ModeratelyE ective

ModeratelyE ective

ModeratelyE ective

ModeratelyE ective

ModeratelyE ective

HighlyE ective

Gulf Mgmt.region / NorthAtlantic /Rakes (wild)

ModeratelyE ective

ModeratelyE ective

ModeratelyE ective

ModeratelyE ective

ModeratelyE ective

ModeratelyE ective

HighlyE ective

Maritimes /North Atlantic/ Rakes (wild)

ModeratelyE ective

ModeratelyE ective

ModeratelyE ective

ModeratelyE ective

ModeratelyE ective

ModeratelyE ective

HighlyE ective

Quebec /North Atlantic/ Rakes (wild)

ModeratelyE ective

ModeratelyE ective

ModeratelyE ective

HighlyE ective

ModeratelyE ective

ModeratelyE ective

HighlyE ective

CANADA / SOUTHERN GULF OF ST. LAWRENCE, RAKES (WILD)GULF MGMT. REGION / NORTH ATLANTIC, RAKES (WILD)MARITIMES / NORTH ATLANTIC, RAKES (WILD)

Moderately E ective

Regulations for the Canadian hard clam and soft-shell clam sheries are set by theDepartment of Fisheries and Oceans Canada (DFO). In the Maritimes and Gulf regions,regulations are set under the Maritimes Provinces Fishery Regulations. Regulations includelicense restrictions, gear restrictions, a closed season from January 1 to March 31, a minimumsize limit (which varies depending on the species and area), and a recreational dailybag/catch limit. Additionally, some clam beds may be closed to shing for conservationpurposes or for contamination reasons (DFO 2001) (Hicks and Ouellette 2011) (DFO 2011b).

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Subfactor 3.1.2 – Recovery of Species of ConcernSubfactor 3.1.2 – Recovery of Species of Concern

Considerations: When needed, are recovery strategies/management measures in place to rebuildover shed/threatened/ endangered species or to limit shery’s impact on these species and what istheir likelihood of success? To achieve a rating of Highly E ective, rebuilding strategies that have ahigh likelihood of success in an appropriate timeframe must be in place when needed, as well asmeasures to minimize mortality for any over shed/threatened/endangered species.

There have been limited population assessments of clams in these regions, so it is di cult todetermine the e ectiveness of these management measures. In some areas, there areconcerns about low clam abundance and over shing. We have therefore awarded a"moderately e ective" score.

QUEBEC / NORTH ATLANTIC, RAKES (WILD)

Moderately E ective

The Department of Fisheries and Oceans Canada (DFO) is responsible for the management ofthe soft-shell clam. In the Quebec region, regulations for the soft-shell clam shery are setthrough a Conservation Harvesting Plan that is updated every 2 years. The commercial sheryis regulated through the number of licenses issued, a minimum size limit of 51 mm, and aseason that runs from March 14 to October 31. Additionally, commercial shers are requiredto ll out logbooks (DFO 2014). The minimum size limit and season also apply to therecreational shery, and there is a daily catch limit of 300 clams for recreational shers (DFO2011). Hand tools are the only gear permitted to harvest clams in this region. Some areashave been closed to clam shing for conservation purposes, and some may also be closed forcontamination reasons (DFO 2014).

Although several management regulations are in place for the soft-shell clam shery inQuebec, their e ectiveness remains uncertain. Low clam abundance has been reported insome areas (DFO 2011). A "moderately e ective" score is awarded.


Moderately E ective

There have been minimal assessments of the hard and soft-shell clam populations in theMaritimes and Gulf regions, so the status of their populations is largely uncertain. In someareas, soft-shell clam abundance has been observed to be low, and there is a suggestion thatover shing has occurred (Hicks and Ouellette 2011). In the past, the Department of Fisheriesand Oceans Canada has closed shing on clams beds with low abundances to allow them torecover (DFO 2001) (Hicks and Ouellette 2011). We have rated this factor "moderatelye ective."

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Subfactor 3.1.3 – Scienti c Research and MonitoringSubfactor 3.1.3 – Scienti c Research and Monitoring

Considerations: How much and what types of data are collected to evaluate the health of thepopulation and the shery’s impact on the species? To achieve a Highly E ective rating, populationassessments must be conducted regularly and they must be robust enough to reliably determine thepopulation status.


Moderately E ective

The status of soft-shell clam in the Quebec region remains uncertain, but abundance hasbeen estimated to be low in some places. Several management regulations are in place tocontrol shing on soft-shell clam (DFO 2011). We have rated this factor "moderately e ective."

CANADA / SOUTHERN GULF OF ST. LAWRENCE, RAKES (WILD)GULF MGMT. REGION / NORTH ATLANTIC, RAKES (WILD)

Moderately E ective

In the Gulf region, there has been limited monitoring of the hard clam and soft-shell clampopulations. The last status update produced by the Department of Fisheries and OceansCanada (DFO) for the Gulf hard clam was in 1996 (DFO 1996a). For the soft-shell clam, DFOevaluated the state of the resource in three areas of Eastern New Brunswick in 2006 bygathering information from local shers, managers, and conservation organizations (Hicksand Ouellette 2011). The last status update on the soft-shell clam resource in Prince EdwardIsland was in 1996 (DFO 1996b). Evaluating clam populations is not considered to be cost-e ective (DFO 2001). The Science Branch of the DFO has conducted a few biological studies onclam populations (DFO 2001). Commercial catch information is collected, but there areconcerns that catches are underreported. Recreational catch information is not collected(Hicks and Ouellette 2011). A "moderately e ective" score is awarded because, although somedata are collected, they are insu cient to ensure the long-term maintenance of these clamspecies.

MARITIMES / NORTH ATLANTIC, RAKES (WILD)

Moderately E ective

In the Maritimes region, there has been limited monitoring of the soft-shell clam population.The last status updates produced by the Department of Fisheries and Oceans Canada for thesoft-shell clam resource in the Maritimes region were in 1996 (DFO 1996c) (DFO1996d). Evaluating clam populations is not considered to be cost-e ective (DFO 2001). TheScience Branch of the Department of Fisheries Oceans Canada (DFO) has conducted a fewbiological studies on clam populations (DFO 2001). Commercial catch information is collected,but there are concerns that catches are underreported. Recreational catch information is notcollected. A "moderately e ective" score is awarded because, although some data arecollected, they are insu cient to ensure the long-term maintenance of the soft-shell clam

26

population.

Subfactor 3.1.4 – Management Record of Following Scienti c AdviceSubfactor 3.1.4 – Management Record of Following Scienti c Advice

Considerations: How often (always, sometimes, rarely) do managers of the shery follow scienti crecommendations/advice (e.g. do they set catch limits at recommended levels)? A Highly E ectiverating is given if managers nearly always follow scienti c advice.


Moderately E ective

In Quebec, population assessments of soft-shell clams are conducted every 3 years. Theassessments utilize information on commercial catches, shing e ort, catch rates, and thesize structure of clams to evaluate the status of soft-shell clam populations. But the datacollected on shing e ort and catch rates are considered uncertain. Additionally, the amountof soft-shell clam caught by recreational shers is not known. Since 2001, the Department ofFisheries and Oceans Canada (DFO) has conducted research surveys on several of Quebec'sclams beds, which has provided further information on soft-shell clam abundance in someareas (DFO 2011). Overall research and monitoring is considered "moderately e ective."

CANADA / SOUTHERN GULF OF ST. LAWRENCE, RAKES (WILD)

Moderately E ective

There have been limited assessments on the hard clam sheries in the Canadian Gulf region,and limited scienti c advice on how to manage the sheries. Regional Clam AdvisoryCommittees (which may consist of a mix of shers, other industry representatives, Indigenousgroups, managers, scientists, and conservationists) have made recommendations onmodifying regulations over the years (DFO 2001). In the 1990s, when the last status reports onhard clams were published, it was noted that a large minimum size limit would be preferableto ensure that females are able to reproduce before being caught (DFO 1996a). It was alsonoted that a maximum size limit could be useful to protect large females, which are capableof producing a greater number of eggs than smaller females (DFO 1996a) (Landry et al. 1999).A large minimum size limit of 50 mm is in place in the Gulf region (pers. comm., DFO GulfRegion Fishery Management 2016). A maximum size limit has not been implemented, butother regulations (including a closed season) have been put in place (DFO 2001) (DFO 2011b).We have awarded a "moderately e ective" score for this factor.

GULF MGMT. REGION / NORTH ATLANTIC, RAKES (WILD)MARITIMES / NORTH ATLANTIC, RAKES (WILD)

Moderately E ective

There have been limited assessments of the soft-shell clam sheries in the CanadianMaritimes and Gulf regions, and limited scienti c advice on how to manage the sheries. Inthese regions, Regional Clam Advisory Committees (which may consist of a mix of shers,

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Subfactor 3.1.5 – Enforcement of Management RegulationsSubfactor 3.1.5 – Enforcement of Management Regulations

Considerations: Do shermen comply with regulations, and how is this monitored? To achieve a HighlyE ective rating, there must be regular enforcement of regulations and veri cation of compliance.

other industry representatives, Indigenous groups, managers, scientists, andconservationists) have made recommendations on modifying regulations over the years (DFO1996c) (DFO 2001). For instance, the advisory committees pushed for limited access licensingto control shing pressure in the 1990s. Other scienti c recommendations have includedusing closed areas to control shing and establishing community-based programs to assistwith clam management (DFO 1996b) (DFO 1996c). But concerns of over shing remain (Hicksand Ouellette 2011). This factor is rated "moderately e ective."


Highly E ective

In Quebec, scienti c recommendations have been provided. Recommendations made basedon the 2007 assessment included protecting population reproductive potential by ensuringthat the 51-mm size limit is respected, limiting shing e ort and harvesting to no more than10% of the biomass, creating refuge areas to protect the reproductive population, utilizing arotating harvest strategy, and increased monitoring (DFO 2008a). Several of theserecommendations have been implemented. For instance, since 2009, three areas havebeen closed to shing to protect reproductive potential, and the 2011 assessment did indicatea decrease in shing e ort. The recommendations following the 2011 assessment againincluded enforcing the minimum size limit, limiting shing to current levels, and documentingthe recreational catch to assess its impact on soft-shell clam populations (DFO 2011). In 2010,the Science Advisory Secretariat recommended that shed clam beds be divided into sectionsand that shers be limited to working in their assigned section (DFO 2011). This wasimplemented in the 2012–2013 sheries regulations for Quebec (Brulotte 2011). Becausescienti c recommendations are generally followed, a "highly e ective" score is awarded.


Moderately E ective

The Department of Fisheries and Oceans Canada (DFO) is responsible for enforcingmanagement regulations. Fishery o cers throughout Canada conduct patrols on land, sea,and in the air to enforce regulations (DFO 2016c). But in the Gulf and Maritimes clam

sheries, there have been concerns about underreporting of landings, and it has been notedthat DFO does not have the resources to monitor landings more adequately (DFO 2001) (Hicksand Ouellette 2011). Enforcement is therefore considered "moderately e ective."

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Subfactor 3.1.6 – Management Track RecordSubfactor 3.1.6 – Management Track Record

Considerations: Does management have a history of successfully maintaining populations atsustainable levels or a history of failing to maintain populations at sustainable levels? A HighlyE ective rating is given if measures enacted by management have been shown to result in the long-term maintenance of species overtime.

Subfactor 3.1.7 – Stakeholder InclusionSubfactor 3.1.7 – Stakeholder Inclusion

Considerations: Are stakeholders involved/included in the decision-making process? Stakeholders areindividuals/groups/organizations that have an interest in the shery or that may be a ected by themanagement of the shery (e.g., shermen, conservation groups, etc.). A Highly E ective rating is givenif the management process is transparent and includes stakeholder input.

Moderately E ective

The Department of Fisheries and Oceans Canada (DFO) is responsible for enforcingmanagement regulations. Fishery o cers throughout Canada conduct patrols on land, sea,and in the air to enforce regulations (DFO 2016c) (DFO 2016b). But in the Quebec soft-shellclam shery, there have been issues with the enforcement of the minimum size limit. Theproportion of undersized clams in the catch often exceeds 15% (DFO 2011). Enforcement istherefore considered "moderately e ective."


Moderately E ective

Clam landings declined in many areas throughout the Maritimes and Gulf managementregions during the 1990s (DFO 1996a) (DFO 1996b) (DFO 1996c) (DFO 1996d). In 1993, theMaritime Provinces Fishery Regulations were implemented, which required commerciallicenses to harvest clams, imposed set shing seasons, and determined allowable gear (DFO2011b). Additionally, minimum sizes were increased in some areas to ensure protection ofreproductive-sized clams (Hicks and Ouellette 2011) (DFO 1996d). Because of limitedmonitoring of clams, it is unknown if the current management system is maintaining clampopulations at adequate levels. This results in a score of "moderately e ective."


Moderately E ective

After a decline in soft-shell clam landings in Quebec between 2000 and 2006, severalmanagement recommendations were implemented to conserve the clam population (DFO2008a). An increase in soft-shell clam catch rates was recorded across most of Quebec from2009 to 2010, but clam abundance is some areas remains low, and assessments are notavailable after 2010 (DFO 2011). We have therefore awarded a "moderately e ective" score.

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Factor 3.2: Bycatch StrategyFactor 3.2: Bycatch Strategy

SCORING GUIDELINES

Four subfactors are evaluated: Management Strategy and Implementation, Scienti c Research andMonitoring, Record of Following Scienti c Advice, and Enforcement of Regulations. Each is rated as‘ine ective,’ ‘moderately e ective,’ or ‘highly e ective.’ Unless reason exists to rate Scienti c Researchand Monitoring, Record of Following Scienti c Advice, and Enforcement of Regulations di erently,these rating are the same as in 3.1.

5 (Very Low Concern)—Rated as ‘highly e ective’ for all four subfactors considered4 (Low Concern)—Management Strategy rated ‘highly e ective’ and all other subfactors ratedat least ‘moderately e ective.’3 (Moderate Concern)—All subfactors rated at least ‘moderately e ective.’2 (High Concern)—At minimum, meets standards for ‘moderately e ective’ for ManagementStrategy but some other factors rated ‘ine ective.’1 (Very High Concern)—Management exists, but Management Strategy rated ‘ine ective.’0 (Critical)—No bycatch management even when over shed, depleted, endangered orthreatened species are known to be regular components of bycatch and are substatntiallyimpacted by the shery


Highly E ective

Clam shery management in the Gulf and Maritimes regions is transparent and involvesstakeholder input. In the Maritimes and Gulf regions, stakeholders are represented throughRegional Clam Advisory Committees, which are made up of commercial and recreational

shers, First Nations leaders, other industry representatives, and scientists. During the 1990s,clam sheries regulations in the Gulf and Maritimes regions of Canada were restructuredwith input from Regional Clam Advisory Committees (DFO 1996c) (DFO 1996d) (DFO 2001). Forexample, regional committees pushed for limited access licensing in the 1990s to bettercontrol shing (DFO 1996c), and dive- shing for clams was banned in Eastern New Brunswickbased on recommendations from shers (DFO 2001). Stakeholder inclusion is thereforescored as "highly e ective."


Highly E ective

The management process for the soft-shell clam shery in Quebec is transparent andincludes stakeholder input (DFO 2008b). In the Quebec region, there is a Liaison Committeebetween DFO and the Quebec Harvesting Sector (DFO 2016a). Stakeholder inclusion istherefore scored as "highly e ective."

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FACTOR 3.2: BYCATCH STRATEGY

Region / MethodAllKept Critical Strategy Research Advice Enforce

Canada / Southern Gulf of St. Lawrence / Rakes(wild)

Yes No

Gulf Mgmt. region / North Atlantic / Rakes (wild) Yes

Maritimes / North Atlantic / Rakes (wild) Yes

Quebec / North Atlantic / Rakes (wild) Yes

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Criterion 4: Impacts on the habitat and ecosystemCriterion 4: Impacts on the habitat and ecosystem

This Criterion assesses the impact of the shery on sea oor habitats, and increases that base score ifthere are measures in place to mitigate any impacts. The shery’s overall impact on the ecosystemand food web and the use of ecosystem-based sheries management (EBFM) principles is alsoevaluated. Ecosystem Based Fisheries Management aims to consider the interconnections amongspecies and all natural and human stressors on the environment.

The nal score is the geometric mean of the impact of shing gear on habitat score (plus themitigation of gear impacts score) and the Ecosystem Based Fishery Management score. The Criterion 2rating is determined as follows:


Rating cannot be Critical for Criterion 4.



SCORING GUIDELINES

Factor 4.1 - Impact of Fishing Gear on the Habitat/SubstrateFactor 4.1 - Impact of Fishing Gear on the Habitat/Substrate

5 (None) - Fishing gear does not contact the bottom4 (Very Low) - Vertical line gear3 (Low)—Gears that contacts the bottom, but is not dragged along the bottom (e.g. gillnet, bottom longline, trap) and is not shed on sensitive habitats. Bottom seine on resilient mud/sand habitats. Midwater trawl that is known to contact bottom occasionally 2 (Moderate)—Bottom dragging gears (dredge, trawl) shed on resilient mud/sand habitats. Gillnet, trap, or bottom longline shed on sensitive boulder or coral reef habitat. Bottom seine except on mud/sand1 (High)—Hydraulic clam dredge. Dredge or trawl gear shed on moderately sensitive

Region / MethodGear Type andSubstrate

Mitigation of GearImpacts EBFM Score

Canada / Southern Gulf of St.Lawrence / Rakes (wild)

3.00: LowConcern

0.25: MinimalMitigation


Yellow(3.122)

Gulf Mgmt. region / North Atlantic /Rakes (wild)

3.00: LowConcern



Yellow(3.122)

Maritimes / North Atlantic / Rakes(wild)

3.00: LowConcern



Yellow(3.122)

Quebec / North Atlantic / Rakes(wild)

3.00: LowConcern



Yellow(3.122)

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habitats (e.g., cobble or boulder)0 (Very High)—Dredge or trawl shed on biogenic habitat, (e.g., deep-sea corals, eelgrassand maerl)Note: When multiple habitat types are commonly encountered, and/or the habitatclassi cation is uncertain, the score will be based on the most sensitive, plausible habitattype.

Factor 4.2 - Mitigation of Gear ImpactsFactor 4.2 - Mitigation of Gear Impacts

+1 (Strong Mitigation)—Examples include large proportion of habitat protected from shing(>50%) with gear, shing intensity low/limited, gear speci cally modi ed to reduce damageto sea oor and modi cations shown to be e ective at reducing damage, or an e ectivecombination of ‘moderate’ mitigation measures.+0.5 (Moderate Mitigation)—20% of habitat protected from shing with gear or othermeasures in place to limit shing e ort, shing intensity, and spatial footprint of damagecaused from shing.+0.25 (Low Mitigation)—A few measures are in place (e.g., vulnerable habitats protected butother habitats not protected); there are some limits on shing e ort/intensity, but notactively being reduced0 (No Mitigation)—No e ective measures are in place to limit gear impacts on habitats

Factor 4.3 - Ecosystem-Based Fisheries ManagementFactor 4.3 - Ecosystem-Based Fisheries Management

5 (Very Low Concern)—Substantial e orts have been made to protect species’ ecologicalroles and ensure shing practices do not have negative ecological e ects (e.g., largeproportion of shery area is protected with marine reserves, and abundance is maintainedat su cient levels to provide food to predators)4 (Low Concern)—Studies are underway to assess the ecological role of species andmeasures are in place to protect the ecological role of any species that plays anexceptionally large role in the ecosystem. Measures are in place to minimize potentiallynegative ecological e ect if hatchery supplementation or sh aggregating devices (FADs) areused.3 (Moderate Concern)—Fishery does not catch species that play an exceptionally large rolein the ecosystem, or if it does, studies are underway to determine how to protect theecological role of these species, OR negative ecological e ects from hatcherysupplementation or FADs are possible and management is not place to mitigate theseimpacts2 (High Concern)—Fishery catches species that play an exceptionally large role in theecosystem and no e orts are being made to incorporate their ecological role intomanagement.1 (Very High Concern)—Use of hatchery supplementation or sh aggregating devices (FADs)in the shery is having serious negative ecological or genetic consequences, OR shery hasresulted in trophic cascades or other detrimental impacts to the food web.

33

Factor 4.2 - Mitigation of Gear ImpactsFactor 4.2 - Mitigation of Gear Impacts

CANADA / SOUTHERN GULF OF ST. LAWRENCE, RAKES (WILD)GULF MGMT. REGION / NORTH ATLANTIC, RAKES (WILD)MARITIMES / NORTH ATLANTIC, RAKES (WILD)QUEBEC / NORTH ATLANTIC, RAKES (WILD)

Low Concern

Hand raking for shell sh can a ect the habitat and associated bottom-living animals in avariety of ways. Because both hard and soft-shell clams are burrowing species, shingrequires disturbance of the sediment (Brown and Wilson 1997). Rakes are driven into thesediment and pulled toward the raker, turning over the substrate to expose clams (Brown andWilson 1997). In addition to exposing the target species, raking can expose other animals andresult in fatal damage to them. The rakes may puncture the shells of undersized ornontargeted shell sh (Kaiser et al. 2001). For instance, in some cases hand-raked areas hadthree times as many damaged clams as areas that were not raked. Additionally, sessileorganisms such as oysters may be buried by sediment as it is turned over and may su ocate(Lenihan and Micheli 2000). Soft-bodied organisms such as worms are extremely sensitive tosediment disturbance; their tubes and burrows may be destroyed by rakes, and as theseorganisms are raked to the surface, they may die from exposure to higher levels of oxygenthan they can tolerate or may become exposed to opportunistic predators. In one study,shell sh raking, even at low intensities, reduced the abundance of three polychaete wormspecies by 54%–77% (Brown and Wilson 1997). Overall, abundance of all species in rakedareas drops immediately (within a day) when raking begins. Recovery of the rakedcommunities depends on the size of the shed area, the type of sediment or substrate (sand,mud ats, etc.), natural disturbances to the habitat, intensity of the shing e ort, andsuccessful spawning and recruitment of a ected species. It may take anywhere from 50 daysto one-and-a- quarter years for an area to recover from shell sh raking (Kaiser et al. 2001).Overall, shell sh raking is considered to have a low to moderate impact on bottom habitats.


Minimal Mitigation

In the Gulf, Maritimes, and Quebec regions, some clams beds are closed for conservationpurposes (and some are closed for contamination reasons). Additionally, there is a closedseason during the winter months (DFO 2001) (Hicks and Ouellette 2011) (DFO 2011b) (DFO2014). Because some e orts have been taken to restrict shing e ort and intensity, we haveawarded a "minimal" mitigation score.

34

FFaaccttoorr 44.1.1 -- IImmppaacctt ooff FFiisshhiinngg GGeeaarr oonn tthhee HHaabbiittaatt//SSuubbssttrraattee


Moderate Concern

Through DFO's Sustainable Fisheries Framework, it has committed to moving toward anecosystem-based management approach (DFO 2016f). But to date, there have been no e ortsto fully assess the ecological impacts of the clam sheries. Clams are not considered speciesof exceptional ecological importance. They are lter feeders, which means they feed by

ltering plankton and suspended particles out of the water. Clams have a variety ofpredators, including sh, crabs, and birds (DFO 2001) (DFO 2008a). Because Canada'secosystem-based sheries management approach remains in the planning stages, this factoris assessed as a "moderate" concern.

35

FFaaccttoorr 44.3.3 -- EEccoossyysstteemm--BBaasseedd FFiisshheerriieess MMaannaaggeemmeenntt

AcknowledgementsAcknowledgements

Scienti c review does not constitute an endorsement of The Sa na Center or Seafood Watch®program, or its seafood recommendations, on the part of the reviewing scientists. The Sa na Centerand Seafood Watch® are solely responsible for the conclusions reached in this report.

The Sa na Center and Seafood Watch would like to thank several anonymous reviewers and Dr.Michael Chadwick (retired), former Regional Director of the Oceans and Science Branch, DFO, GulfRegion for graciously reviewing this report for scienti c accuracy.

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northern quahog and soft-shell clam - the safina...

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