Seafood Watch Seafood Report

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1 Seafood Watch Seafood Report Commercially Important Atlantic Flatfishes Summer flounder (Paralichthys dentatus) Winter flounder (Pseudopleuronectes americanus) Witch flounder (Glyptocephalus cynoglossus) Yellowtail flounder (Limanda ferruginea) Windowpane flounder (Scophthalmus aquosus) American plaice (Hippoglossoides platessoides) Atlantic halibut (Hippoglossus hippoglossus) Atlantic halibut, Illustration Monterey Bay Aquarium Final Report June 25, 2004 Stock Status Update January 4, 2011 Melissa Mahoney Stevens Fisheries Research Analyst (former) Monterey Bay Aquarium

2 Seafood Watch Atlantic Flatfishes Report January 4, 2011 About Seafood Watch and the Seafood Reports Monterey Bay Aquarium s Seafood Watch program evaluates the ecological sustainability of wild-caught and farmed seafood commonly found in the United States marketplace. Seafood Watch defines sustainable seafood as originating from sources, whether wild-caught or farmed, which can maintain or increase production in the long-term without jeopardizing the structure or function of affected ecosystems. Seafood Watch makes its science-based recommendations available to the public in the form of regional pocket guides that can be downloaded from the Internet (seafoodwatch.org) or obtained from the Seafood Watch program by ing seafoodwatch@mbayaq.org. The program s goals are to raise awareness of important ocean conservation issues and empower seafood consumers and businesses to make choices for healthy oceans. Each sustainability recommendation on the regional pocket guides is supported by a Seafood Report. Each report synthesizes and analyzes the most current ecological, fisheries and ecosystem science on a species, then evaluates this information against the program s conservation ethic to arrive at a recommendation of Best Choices, Good Alternatives or Avoid. The detailed evaluation methodology is available upon request. In producing the Seafood Reports, Seafood Watch seeks out research published in academic, peer-reviewed journals whenever possible. Other sources of information include government technical publications, fishery management plans and supporting documents, and other scientific reviews of ecological sustainability. Seafood Watch Fisheries Research Analysts also communicate regularly with ecologists, fisheries and aquaculture scientists, and members of industry and conservation organizations when evaluating fisheries and aquaculture practices. Capture fisheries and aquaculture practices are highly dynamic; as the scientific information on each species changes, Seafood Watch s sustainability recommendations and the underlying Seafood Reports will be updated to reflect these changes. Parties interested in capture fisheries, aquaculture practices and the sustainability of ocean ecosystems are welcome to use Seafood Reports in any way they find useful. For more information about Seafood Watch and Seafood Reports, please contact the Seafood Watch program at Monterey Bay Aquarium by calling Disclaimer Seafood Watch strives to have all Seafood Reports reviewed for accuracy and completeness by external scientists with expertise in ecology, fisheries science and aquaculture. Scientific review, however, does not constitute an endorsement of the Seafood Watch program or its recommendations on the part of the reviewing scientists. Seafood Watch is solely responsible for the conclusions reached in this report. Seafood Watch and Seafood Reports are made possible through a grant from the David and Lucile Packard Foundation. 2

3 Seafood Watch Atlantic Flatfishes Report January 4, 2011 Executive Summary Commercially important Atlantic flatfishes comprise a significant portion of groundfish trawl landings along the Atlantic seaboard of Canada and the U.S. The groundfish fishery in New England is probably the oldest U.S. fishery, operating for more than 400 years. Participants historically targeted cod, haddock, Atlantic halibut and other flounders, shifting effort to new areas as stocks were depleted. Groundfish landings have been variable throughout the last two centuries, but when fishing pressure intensified in the 1960s, many stocks, including the flounders, were depleted to low levels, despite the implementation of a Fishery Management Plan in The problem stems mainly from 1) overcapitalization of the fleet and 2) fishing mortality consistently above a sustainable level. Most of the flounders evaluated in this report are inherently resilient to fishing pressure, as they are relatively fast growing and reach maturity within 5 years. Of the 12 flounder stocks, 8 stocks are overfished and 7 stocks are experiencing overfishing (6 of these are overfished). Windowpane flounder (Southern New England/Mid Atlantic SNE/MA) has a poor stock status according to Seafood Watch because overfishing is occurring and the stock is not currently overfished but substantially below B MSY. Winter flounder (Gulf of Maine GOM) also has a poor stock status according to Seafood Watch. While GOM winter flounder is classified as having an unknown status, experts believe that the stock is substantially overfished with overfishing occurring, and trends in abundance are down. Winter flounder (Georges Bank GB and SNE/MA), Witch flounder, Yellowtail flounder (SNE/MA), Yellowtail (CC/GOM), Yellowtail (GB), Windowpane flounder (GOM/GB), and Atlantic halibut all have critical stock status according to Seafood Watch because they are overfished with overfishing occurring with the exception of Atlantic halibut, which is overfished with a variable trend in abundance. Summer flounder are not overfished, are moderately below target levels, and overfishing is not occurring, resulting in a moderate ranking for stock status according to Seafood Watch. American plaice also technically would receive a moderate ranking for stock status according to Seafood Watch criteria; however, these fish are caught in a multi-species fishery with stocks in poor or critical condition, such as witch flounder, and fishing pressure directed at American plaice also increases pressure on these depressed stocks. Thus, stock status of all Atlantic flounders other than the summer flounder is ranked poor, while summer flounder stock status is ranked moderate. Trawling is the most common fishing method utilized for capture of groundfishes. This method results in significant disturbance to the sea floor, impacting marine habitats critical to the survival of groundfishes and other species. The severity of impact depends upon gear components and the resiliency of the habitat type being trawled. Trawling is indiscriminate, and along with targeted groundfish the gear takes unmarketable, illegal, or undersized species that are fatally discarded, adding to the overall fishing mortality of many groundfish species. Managers of groundfish stocks have attempted to mitigate both habitat effects and bycatch from trawling operations by closing over 25,000 square miles of ecologically sensitive habitat to trawling, increasing mesh size for the trawl gear, and including discard estimates in fishing mortality analyses. In addition, managers actively observe stock abundance patterns and have implemented several regulations over the years in an attempt to maintain stock productivity. However, the management regime has not prevented significant declines of many flounder 3

4 Seafood Watch Atlantic Flatfishes Report January 4, 2011 species. Due to the poor to critical status of the stocks and the severe habitat/ecosystem impacts, all Atlantic flatfishes are recommended as Avoid, except summer flounder, which is recommended as a Good Alternative. This report was updated on January 4, Please see Appendix III for a summary of changes made at this time. Table of Sustainability Ranks Conservation Concern Sustainability Criteria Low Moderate High Critical Inherent Vulnerability Status of Stocks Nature of Bycatch Habitat Effects Management Effectiveness Summer flounder American plaice, Winter (GOM), Windowpane (SNE/MAB) Winter (GB), Winter (SNE/MA), Witch flounder, Yellowtail (SNE/MA), Yellowtail (CC/GOM), Yellowtail (GB), Windowpane (GOM/GB), Atlantic halibut About the Overall Seafood Recommendation: A seafood product is ranked Best Choice if three or more criteria are of Low Conservation Concern (green) and the remaining criteria are not of High or Critical Conservation Concern. A seafood product is ranked Good Alternative if the five criteria average to yellow (Moderate Conservation Concern) OR if the Status of Stocks and Management Effectiveness criteria are both of Moderate Conservation Concern. A seafood product is ranked Avoid if two or more criteria are of High Conservation Concern (red) OR if one or more criteria are of Critical Conservation Concern (black) in the table above. 4

5 Seafood Watch Atlantic Flatfishes Report January 4, 2011 Overall Seafood Recommendation: Seafood Watch Recommendation Good Alternative Summer flounder Avoid American plaice, winter flounder, witch flounder, yellowtail, windowpane, Atlantic halibut Introduction Flatfishes are a distinct group, consisting of 11 families, 123 genera and about 570 species worldwide (Nelson 1994). As the name implies, individuals in this order (Pleuronectiformes) generally lay flat, with skull development in the larval stage causing the migration of one eye around the head and distinct pigmentation between sides (bottom-facing side white, upwardfacing side pigmented for camouflage). Flounders, soles, turbots, halibuts, sanddabs, plaices, and tonguefishes are included under the auspice of flatfish ; when combined with provincial common names, taxonomy can become confusing. Most commercially important flatfishes in the Atlantic are from the family Pleuronectidae (right-eye flounders), composed of 21 genera and 60 species, including witch, winter, and yellowtail flounder, American plaice and Atlantic halibut (Collete and Klein-MacPhee 2002). Other important families are Paralichthyidae (lefteyed sand flounders, including summer flounder) and Scophthalmidae (windowpane flounder). Except for summer flounder, which is managed under a separate Fishery Management Plan (FMP), all other commercially important Atlantic flatfishes are regulated under the New England Multispecies Groundfish FMP, which manages the catch of 15 species and 24 stocks along the U.S. Atlantic coast (Fig. 1). States also actively manage nearshore stocks, particularly summer and winter flounder, as they pertain to recreational fisheries along the coast. 5

6 Seafood Watch Atlantic Flatfishes Report January 4, 2011 Figure 1. Map of the northwest Atlantic, including the major subregions (NEFSC). The New England groundfish fishery has existed since colonial times. The first colonial fishermen used small sailing dories and caught mostly cod by hook and line, salting their product as a means of preservation (Collete and Klein-MacPhee 2002). Sailboats gave way to steamships, and the use of otter trawls (from Europe) and on-board refrigeration beginning in the early 1900s revolutionized the fishery (NRC 1998). After World War I, fishers began to target a wider variety of species, including haddock, yellowtail and winter flounders, as well as Atlantic halibut. Groundfish landings decreased during World War II, and then increased in the 1960s, particularly due to effort by distant-water factory trawlers from Russia and Spain. Prompted by concerns about overfishing, the U.S. created the first 200-mile Exclusive Economic Zone (EEZ) along its Atlantic coastline in 1977, and thereafter encouraged the growth of the U.S. fishery. Canada also created a 200-mile EEZ. Conflicts persisted over the U.S./Canada maritime boundary until the establishment of the Hague Line in 1985 (NRC 1998). Once the U.S. EEZ was established, domestic fishing grew exponentially. From 1975 to 1980, the number of vessels in the U.S. groundfish fleet nearly doubled, from around 600 to over 1,100 (Brodziak and Link 2002). Fishing pressure continued to intensify as technology advanced and fishing capital increased. Exploitation rates were highest in the early 1990s, the same year that stock biomass reached record lows (Collete and Klein-MacPhee 2002). Lawsuits were filed against the Department of 6

7 Seafood Watch Atlantic Flatfishes Report January 4, 2011 Commerce (DOC, the parent agency for the National Marine Fisheries Service, which governs U.S. fish stocks), alleging the DOC failed to protect natural resources. Severe restrictions and subsequent economic hardship followed; fishing effort was limited through closed areas, reduced quotas, and government-subsidized boat buyback programs. These measures have not yet achieved the goal of reviving depleted stocks. The New England groundfish fishery is currently implementing new management options (Amendment 13), again brought about by litigation (CLF et al. vs. NMFS et al., December 2001) aimed at drastically decreasing fishing effort to bring about recovery of several depleted groundfish stocks. Scope of the analysis and the ensuing recommendation: There are many commercially important flatfishes caught in the Atlantic basin. This report focuses on the primary flatfish species landed and sold on the U.S. market, either currently or historically (e.g., Atlantic halibut), many of which are also landed in Eastern Canadian provinces (Newfoundland and Labrador) and other North Atlantic countries (Norway, etc.) and imported to the U.S. The status of Canadian stocks is only briefly mentioned in this report; recommendations are specific to U.S. flatfish stocks. Availability of Science Because flatfish are valuable to the New England and Canadian economies, life history and abundance information is available for most flatfish species. One issue of concern for some species is the degree of mixing between stocks in different areas of the Atlantic, as separate stocks are managed under distinct management plans. Further research on migration patterns, spawning behavior (coinciding with oceanographic data), and genetics may better confirm the ranges of individual stocks. Intrinsic rate of increase, r, was not found for any Atlantic flatfish species in conducting the research for this report. Some fecundity and longevity data was also not available for minor species, and from preliminary literature research it does not appear that maximum age has been validated for any species discussed in this report. Market Availability Common/Market Names Atlantic flatfishes are sold under a variety of names: summer flounder is sold as fluke; winter flounder is sold as lemon sole, blackback, and dab; witch flounder is sold as gray sole; American plaice is sold as dab; yellowtail flounder is sold as rusty flounder; and windowpane flounder is sold as sand dab. When used for sushi or sashimi, Atlantic flatfishes are commonly sold as hirame. Seasonal Availability Flatfishes may be found year round in both retail and service markets. Product Forms Flatfishes may be marketed as fresh or frozen fillets, blocks, whole, or value-added (i.e., breaded). 7

8 Seafood Watch Atlantic Flatfishes Report January 4, 2011 Product Sources In 2002, approximately 206,160 mt of flatfish were landed at U.S. ports (NMFS 2003). Of that amount, approximately 29,000 mt were of Atlantic origin; the bulk of the catch consisted of Pacific halibut (Hippoglossus stenolepis) and soles (Yellowfin, Limanda aspera; rock sole, Lepidopsetta bilineata; and flathead sole, Hippoglossoides elassodon). Approximately 5,770 mt of flatfish landed were of unknown origin. The U.S. exported 68,014 mt of flatfishes worth over US$125 million, consisting mainly of Pacific halibut. Also, about 265 mt of imports were reexported; product entered the U.S. and was redirected to outside the country without significantly changing form. The U.S. experienced a negative trade balance of approximately US$78 million, representing over 22,000 mt of flatfish product. Consequently, the total U.S.- caught flatfish product available on the U.S. market was approximately 138,150 mt. In 2002, the U.S. imported almost 46,000 mt of flatfishes from several countries, most notably Canada and China (Fig. 2). The value of this product was over US$204 million. Canadian exports of flatfish to the U.S. consisted mainly of winter, witch, and yellowtail flounder, and American plaice, fisheries for which operate off the coasts of Labrador, Newfoundland and Nova Scotia (Gulf of St. Lawrence). Atlantic halibut, also targeted in Canada s northeast fisheries, comprised approximately 4% (1,049 mt) of flatfish exports to the U.S., indicating greater effort for Atlantic halibut than in Canadian fisheries than in U.S. fisheries (10 mt in 2002). The origin of Chinese flatfish imports is unknown, as they are not identified by species 1. 24,906 USA 138,148 11,499 9,549 CANADA CHINA OTHERS Figure 2. Total flatfish available to U.S. market: domestic (U.S. landings minus exports), and imports of flatfish seafood products, 2002 (NMFS 2003). 1 The majority of Chinese flatfish imports were recorded as sole, which is likely to be of Pacific origin, since several species of sole (rock, yellowfin, flathead, etc.) are landed in high volume in the Bering Sea/Gulf of Alaska region. 8

9 Seafood Watch Atlantic Flatfishes Report January 4, 2011 Analysis of Seafood Watch Sustainability Criteria for Wild-Caught Species Criterion 1: Inherent Vulnerability to Fishing Pressure Atlantic flatfish possess variable life history characteristics. Generally speaking, these fishes reach maturity at a young age (< 5 yrs), experience a moderate lifespan (10-30 yrs), and exhibit relatively high fecundity (Table 1). Most flatfish species are fairly sedentary, but exhibit seasonal onshore/offshore movements, as well as ontenogenic shifts towards deeper habitat with age (Collete and Klein-MacPhee 2002). As described in Table 1, many species occupy a large latitudinal range and exhibit phenotypic differences between geographical areas. A general trend of later age at maturity, lower fecundity, and slower growth has been observed for more northerly-ranging and deeper-dwelling stocks (Cargnelli et al. 1999b; Pereira et al. 1999; Collete and Klein-MacPhee 2002). Some species stocks (particularly winter and yellowtail flounder), therefore, are distinct between geological regions (e.g., Georges Bank, Gulf of Maine, etc.). Research is still being conducted to ascertain the degree of mixing between stocks. 9

10 Table 1. Life history information for flounders evaluated in this report (Collete and Klein-MacPhee 2002). COMMON NAME SPECIES RANGE 2 GROWTH RATE/MAX SIZE Summer flounder / fluke Winter flounder / Lemon sole Nova Scotia to FL; CoA: CC- >C Hatteras Labrador to GA; CoA: Gulf St. Lawrence to CB, inshore waters from MA to NJ Differs geologically, females may attain 26lbs, 94cmTL To 64cm TL; k = (m), (f) AGE at MATURITY LONGEVITY FECUNDITY Literature males: 50% 1yr, 25cm; females: 50% 1.5 yr, 28cm L50=25cm, A50=1.9yr (GB); L50=28cm(f), 29cm(m), A50=3.3(m)-3.5(f) (CC) 9 yrs 14 yrs Reproductive females range.5-4 million ova per fish (depends on fish size) 99,000 3 million eggs, spawn over 2- mo period (winter to spring) Terceiro 2001; 2003 Pereira et al. 1999; Nitschke et al. 2000; NEFSC 2003 Witch flounder / gray sole Yellowtail flounder Labrador to GB and cont. shelf waters to CH, NC; CoA: GOM/GB Labrador to CB; CoA: western GB & GOM, east CC, SNE To 78 cm, avg 30-51cm To 60cm American plaice Labrador to RI in deep water slow Windowpane flounder Atlantic halibut Gulf St. Lawrence to FL; CoA: GB & SNE N Labrador S to Long Island; CoA: S GB & Scotian Shelf To 51 cm, avg 25-30cm sex dimorphic, to 150 lbs; ~ 320kg males: 50% 3.6yrs, 25.3cm; females: 50% 4.4yrs, 30.4cm females: 26-40cm TL at 2-4 yr in southern range, 5-8 yrs north age 4-7y & 16 cm (male), age 9-15y & 36 cm (fem) A50% = 3 yrs; L50% = 22.2cm (mal), 22.5cm (fem) A50% = 8m/12f yrs; L50% = 80cm (mal), 120cm (fem) 25 yrs Unknown 12 yrs 24-30y (uncertain) Unknown to 50 yrs 350,000-4,570,000 eggs depending on body size 500,000-2,200,000 eggs depending mostly on size Peak spawn from May - Oct 0.5-7mil eggs & >1 batch per season Wigley 2000; Wigley et al. 2003; Froese & Pauly 2003 Cadrin 2000; Johnson et al. 1999; Froese & Pauly 2003; NEFSC 2003 O'Brien 2000; DFO 2002 Hendrickson 2000; (NEFSC 2002a); B&S 2002 (Cargnelli et al. 1999a) 2 CoA = Center of Abundance; CC = Cape Cod; CH = Cape Hatteras; CB = Chesapeake Bay; GB = Grand Banks; GOM = Gulf of Maine; SNE = Southern New England 10

11 Synthesis Most of the flatfishes discussed in this report have a relatively low age at maturity (<5 yrs, possibly with the exception of northerly ranging stocks), moderate (10-30 yrs) or unknown longevity, and a broad latitudinal range throughout the Atlantic Ocean basin. Most of these species are prolific spawners, broadcasting thousands to millions of eggs every year (larval mortality is unknown but presumed to be normal/high). These species of flatfish, therefore, are considered resilient to fishing pressure. Inherent Vulnerability Rank: Resilient Moderately Vulnerable Vulnerable Criterion 2: Status of Wild Stocks Most flounder stocks managed under the Groundfish FMP have been overfished at some point in recent years, with stock biomass consistently below rebuilding targets. Table 2 describes the most current classification status, biological reference points and thresholds, as well as abundance trends and stock structure. About half of the stocks discussed here are in need of fishing mortality (F) reductions in order to rebuild biomass (B). Summer flounder Summer flounder is important to both commercial and recreational fishers, mainly south of Rhode Island (Collete and Klein-MacPhee 2002). Summer flounder is not closely associated with other, depressed stocks of flatfish, but instead is associated and managed with scup and black sea bass (Gabriel 1992; Musick and Mercer 1977), both of which are not overfished with no overfishing occurring (NMFS 2010). An estuarine-dependent species, summer flounder migrate to inshore bays during the summer, and migrate offshore for the winter, and are thus caught in both state (0-3 miles offshore) and federal (3-200 miles offshore) waters. Total U.S. commercial landings of summer flounder from Maine to North Carolina peaked in 1979 at nearly 18,000 mt (Terceiro 2003). Since 1980, 70% of the commercial landings of summer flounder have come from the U.S. EEZ (i.e., greater than 3 miles from shore). With the implementation of the annual commercial landings quota in 1993, commercial landings have become concentrated during the first calendar quarter of the year, with about 50% of the landings taken during the first quarter (SAW ). The reported commercial landings in 2008 were 4,143 mt (Fig. 3), about 3% less than the commercial quota. Recreational landings made up about 39% of the total landings from Recreational landings have exceeded the commercial landings in some recent years, partially due to regulations. The estimated recreational landings in 2007 of 4,445 mt were about 40% over the 2007 quota of 3,030 mt. Summer flounder are also being cultured in some states (Collete and Klein-MacPhee 2002). Analyses of the recreational fishery and aquaculture operations are not included in this Seafood Watch report. For example, in 2000, the commercial catch was limited to 5,000 mt, while that same year 7,100 mt were caught recreationally (Terceiro 2001) 11

12 Spawning stock biomass (SSB) for summer flounder declined 72% from 1983 to 1989 (18,800 mt to 5,200 mt), but has since experienced a sharp increase to an estimated 46,029 mt in 2008 (Terceiro 2009). The age structure of the spawning stock biomass has also expanded. The composition of fish of age 3 or older has increased from less than 10% of the population in 1993 to 68% in 2007 (SAW )). The mean size of fish landed in the Northeast Region commercial fishery has been increasing since 1993 (SAW ), and recent recruitment per unit of SSB has been lower than that estimated at a comparable level of SSB during the early 1980s (SAW ). SSB declined from 24,647 mt in 1982 to 7,017 mt in SSB increased to 43,932 mt by 2004, and was estimated to be 46,029 mt in 2009 (SAW ; Terceiro 2009). This SSB is approximately 77% of SSB MSY (60,074 mt) (Fig. 4). The most recent assessment in 2008 estimated F to be 0.25, 81% of F MSY (0.310) (Fig. 4) (SAW ). Thus, the summer flounder stock is not overfished, and is not subject to overfishing (Terceiro 2009). According to Seafood Watch criteria, this stock is considered a moderate conservation concern, as the current biomass moderately below SSB MSY and overfishing is not occurring. Figure 3. Summer flounder total catch (Figure from Terceiro 2009). 12

13 A) B) Figure 4. (A) Total catch and fishing mortality, and (B) Spawning stock biomass (SSB) and recruitment (millions of fish at age 0) for summer flounder (Figures from SAW 47, 2008). Winter flounder Tagging studies, meristic observations and life history characteristics indicate the existence of separate winter flounder stocks north of Cape Cod, east and south of Cape Cod, and on Georges Bank (see Fig. 1). These seemingly autonomous stocks are managed separately as 1) Gulf of Maine (GOM), 2) Southern New England Middle Atlantic Basin (SNE/MAB), and 3) Georges Bank (GB). All three stocks are managed in federal waters (U.S. EEZ) by the New England Fisheries Management Council (NEFMC) under the Northeast Multispecies Groundfish FMP, Large-mesh portion. In state waters, management has been overseen by the Atlantic States Marine Fisheries Commission s FMP for Inshore Stocks of Winter Flounder since approval in May 1992 (Nitschke et al. 2000). Winter flounder are targeted recreationally in coastal areas with hook and line and commercially offshore mainly with otter trawls (Nitschke et al. 2000; NEFSC 2003a). The state of Massachusetts has historically landed and currently lands a majority of the winter flounder catch (NEFSC 2003a). Winter flounder is often taken incidentally in fisheries for species such as Atlantic cod (Gadus morhua), haddock (Melanogrammus aeglefinus), and yellowtail flounder (NEFSC 2003a). Landings peaked at 15,000 mt in 1966, declined through the 1970s, and then peaked again at 17,500 mt in Landings then steadily declined to a record low of 4,000 mt in Landings have since increased to over 6,000 mt in

14 Gulf of Maine winter flounder stock The Gulf of Maine stock complex extends along the coast of eastern Maine to Provincetown, Massachusetts. Commercial landings were near 1,000 mt from 1964 to the mid 1970s. Thereafter, landings increased to a peak of 2,793 mt in 1982, and then steadily declined to a record low of 253 mt in Landings were near 500 mt from 2000 to Landings declined to a record low in 2006 (200 mt), and remained low in 2007 at 260 mt (NEFSC 2008). Otter trawl was the primary commercial gear used during (>95% of the landings). From , landings from gillnets increased to 25%, reducing the landings from otter trawls to 75% of the catch (Fig. 5) (NEFSC 2008). Figure 5. Commercial landings for Gulf of Maine Winter Flounder by gear, (Figure from NEFSC 2008). Low indices of abundance and the absence of large fish in government surveys led researchers to conclude that the stock was overexploited throughout the mid 1990s. SSB exhibits a long-term declining trend from 1980 to present but has been variable over the past 10 years, increasing from 1995 to 2001, declining from 2001 to 2005, and then increasing from 2005 to 2007 (Fig. 6) (NEFSC 2008). The most recent stock assessment was conducted in The 2007 assessment concluded that the stock is overfished (SSB 2007 /SSB MSY =0.29) and subject to overfishing (F 2007 /F MSY =1.42) (NEFSC 2008). However, conflicting trends existed between the catch data and the survey indices used in the assessment models. Additionally, there was a lack of robust data pertaining to recruitment and catch at age and length, resulting in a high degree of uncertainty. For these reasons, the assessment s findings were not accepted by the Review Panel (RP) (O Boyle 2008). While the relative biomass and biological reference points could not be accurately determined, the RP still expressed grave concerns about the overall status of GOM winter flounder. The RP 14

15 concluded that it is highly likely that biomass is below B MSY, and that there is a substantial probability that it is below 1 2 B MSY (NEFSC 2008). Additionally, the assessment indicated that the stock is less resilient to exploitation then previously thought (O Boyle 2008). Size distribution for GOM winter flounder appears to be normal, except for fish ages 8 and older. For this age class, the average weight has decreased by approximately ½ kilogram since 1992 (NEFSC 2008). Age and sex distributions are unknown. Overall, the stock status Gulf of Maine winter flounder is considered poor according to Seafood Watch criteria because although the stock status is unknown, there is high probability that overfishing is occurring and the stock is overfished (B MSY ), and trends in abundance are down. Seafood Watch also recommends that GOM winter flounder be carefully monitored for any changes in stock status and abundance. Figure 6. Spawning stock biomass (SSB, '000 mt) and recruitment (millions of fish at age-1) for Gulf of Maine winter flounder (Figure from NEFSC 2008). Georges Bank winter flounder stock Total commercial landings of Georges Bank winter flounder come mainly from U.S. fleets, but prior to 1977 also included landings from Canadian and other foreign fleets. Between landings by Canadian vessels increased from 6-24% of total landings (529 mt). The increasing trend in landings primarily occurred in the second half of the year, because there had been a Canadian prohibition on groundfish trawling in Georges Bank from January May (Eeckhaute 15

16 and Brodziak 2005; NEFSC 2008). Since 2001, Canadian landings have declined sharply from 10% (2002) to 1.5% (2007) of total landings. The most recent assessment for GB winter flounder was conducted in 2007 at the Groundfish Assessment Review Meeting (GARM III) (NEFSC 2008). This assessment was based on biomass indices from the NEFSC autumn ( ) and spring ( ) bottom trawl surveys. Relative biomass and abundance indices during the NEFSC fall surveys show a longterm variable trend increasing during the 1970s, followed by a decline during the 1980s and reaching an all-time low in 1991, increasing throughout the 1990s, and decreasing again until 2006 (Fig. 7a). NEFSC spring surveys exhibit more inter-annual variability, with the lowest levels on record for both the U.S. and Canadian relative abundances during (Fig. 7b). Length and weights-at-age were estimated through market sampling but no clear trends were shown. The overfished threshold for GB winter flounder is 50% of B MSY and the overfishing threshold is F MSY = 1.0 (Mayo and Terceiro 2005). The 2007 fishing mortality rate (0.28) was 108% of F MSY (0.26); therefore, overfishing is occurring (NEFSC 2008; NMFS 2010). Additionally, the spawning stock biomass in 2007 (4,964 mt) was 31% of B MSY (16,000 mt), and as such, the stock is overfished (NEFSC 2008). According to Seafood Watch the GB winter flounder stock is a critical conservation concern because the stock is overfished and overfishing is occurring. Figure 7. Trends in relative biomass and abundance indices for GB winter flounder during (A) NEFSC Fall bottom trawl surveys and (B) NEFSC spring and Canadian bottom trawl surveys (Figure from NEFSC 2008). 16

17 Southern New England Middle Atlantic Basin winter flounder stock The majority of winter flounder landings come from the SNE/MAB stock. According to the Working Group on Re-Evaluation of Biological Reference Points for New England Groundfish (RPWG), which re-estimated the biological reference points for SNE/MAB winter flounder in 2002: Fully recruited fishing mortality in 2001 was 0.51 (exploitation rate =37%), about 60% above the RPWG re-estimate of F MSY = Total commercial landings peaked at 11,977 mt in 1966, declined throughout the 1970s, and then increased again in 1981 (11,176 mt). Since then, commercial landings have shown a general decline (2,128 mt in 1994 and 4,556 mt in 2001) (NEFSC 2008). Landings reached a record low of 1,320 mt in 2005, but have increased slightly to 1,622 mt in 2007 (Fig. 8) (NEFSC 2008). The long and short-term trends in spawning stock biomass (SSB) are variable (Fig. 9). In 2007, SSB was estimated to be 3,368 mt (or 7.4 million pounds), about 9% of the re-estimate of B MSY (38,761mt) (Fig. 9). Recent recruitment to the stock has been below average since 1989, and the 2007 year class was estimated to be 8.8 million fish (NEFSC 2008). Fishing mortality (F) in 2007 was estimated to be 0.649, over twice the F MSY proxy (0.248) (NEFSC 2008). The most recent 2007 assessment reported that the stock complex is overfished and overfishing is occurring (NEFSC 2008; NMFS 2010). Therefore, according to Seafood Watch criteria, the stock status of SNE/MA winter flounder is a critical conservation concern. Figure 8. Commercial landings and discards, recreational landings and discards, and total catch for SNE/MA winter flounder stock complex (Figure from NEFSC 2008). 17

18 Figure 9. Spawning stock biomass (SSB, mt) for SNE/MA winter flounder from Figure taken from the NEFSC GARM 2008 (Figure from ASMFC 2009). Witch flounder The most recent assessment for witch flounder was conducted at the GARM III meeting in 2007 (NEFSC 2008). Witch flounder is managed as a single stock by the NEFMC under the Northeast Multispecies Groundfish FMP. A substantial proportion of U.S. landings are from otter trawls in Georges Bank and the Gulf of Maine. In comparison, Canadian landings from these areas have been relatively minor (less than 70 mt annually) (NEFSC 2008). Fishing mortality (F) has shown a declining trend since 2004 (Fig. 10) (NEFSC 2008). Current fishing mortality (F 2007 ) is 0.29, which is 145% of the F MSY proxy (0.20) (NEFSC 2008). From , witch flounder spawning biomass (SSB) had begun to rebound from the historic lows observed in the mid-1990s, mostly due to increased survival of juvenile fish. However, SSB has followed a declining trend since 2000 (6,874 mt in 2000 to 4,575 mt in 2005 and 3,434 mt in 2007) (Fig. 11). This current estimate (B 2007 = 3,434 mt) represents 30% of B MSY (11,447 mt). At present, the stock is overfished and overfishing is occurring (NEFSC 2008; NMFS 2010). According to Seafood Watch criteria, witch flounder is a critical conservation concern. 18

19 Figure 10. Trend in catches and fishing mortality for witch flounder, (Figure from NEFSC 2008). Figure 11. Trends in recruits and SSB for witch flounder (Figure from NEFSC 2008). Yellowtail flounder The yellowtail fishery first developed off southern New England in the 1930s, about the same time as winter flounder abundance declined and the use of otter trawls increased, all due to demand for food products during World War II (Scott 1954, Royce et al in NEFSC 2003a). The fishery expanded into the mid-atlantic, Georges Bank and Cape Cod (CC) stocks in the late 1930s early 1940s. Total landings throughout much of the 1940s were over 20,000 mt annually, but the 1950s saw a huge drop with less than 2,000 mt per year (NEFSC 2003a). Industrial and foreign fishing put immense pressure on groundfish stocks throughout the 1960s 19

20 and early 1970s until foreign vessels were prohibited from these regions in Although foreign effort was eliminated, domestic effort increased, resulting in a net increase in fishing pressure, and landings were generally low in the 1980s and early 1990s. Over the last years of the fishery, landings (and effort) have shifted from SNE/MA to the GB, and then to CC as stocks were depleted. There are minimal recreational landings of yellowtail flounder. Currently, three stocks of yellowtail flounder are recognized in U.S. waters: Georges Bank (GB); SNE/MAB (which were once separate, but now thought to be mixed); and Cape Cod (CC). Evidence of separate stocks is based on tagging studies, geographic information, and early life history studies showing phenotypic variation among areas (NEFSC 2003a). Southern New England Middle Atlantic Basin yellowtail flounder stock The SNE/MAB stock has been fished heavily for over 70 years (NEFSC 2003a). Landings have fluctuated widely over this time due to demand and abundance, but there has been a general decline in landings since the 1970s. The lowest annual landings on record were 200 mt, landed in 1995 (Fig. 12). The proportion of landings between SNE and MAB areas have shifted over time from 10% coming from the MAB in the early 1990s to 70% in 1997 (NEFSC 2003a). Catch-at-age data indicates abundant recruitment in the 1960s and early 1970s, a few strong year classes in 1980 and 1987, and relatively truncated age structure since the early 1970s (NEFSC 2003a). Throughout the 1980s and early 1990s, the fishing mortality rate was around 70%, and yellowtail older than age 4 were rare in both commercial landings and bottom trawl survey catches. Fishing mortality decreased to about 16% in 1998, however, mortality still exceeded the management target chosen to allow stock rebuilding. In 2007, fishing mortality was 0.413, which was 1.65 times that of F MSY (0.25) (NEFSC 2008). Spawning stock biomass decreased from 21,900 mt in 1989 to 400 mt in 1994, but increased to 3,600 mt by In 2007, SSB was 3,508 mt, 13% of SSB MSY (27,400 mt). These current estimates show that the SNE/MAB stock of yellowtail continues to be overfished and overfishing is still occurring (NEFSC 2008). As such, the stock is a critical conservation concern according to Seafood Watch. 20

21 Figure 12. Total catch (mt) for SNE/MA yellowtail flounder (Figure from NEFSC 2008). Cape Cod/Gulf of Maine yellowtail flounder stock The CC/GOM fishery developed after SNE/MAB stocks had declined, and became the most productive stock in the 1990s. Yellowtail and other groundfish are targeted in the shallower waters of Cape Cod and the Gulf of Maine (10-60 m) using primarily otter trawls and some gillnets (NEFSC 2003a). Landings, mainly from Cape Cod, fluctuated between 1,500 2,000 mt from the mid-1960s to the mid-1970s, peaked at a high of 5,100 mt in 1980, and then declined to just 600 mt in 1993 (Fig. 13). From 1994 to 1998, landings averaged 1,100 mt (Cadrin 2000), increasing to 2,439 mt in Since then, landings have decreased, and by 2007 had returned to the historical lows of the late 1930s, only totaling 483 mt (NEFSC 2008). Both state and federally conducted trawl surveys indicated a peak spring survey biomass index in 1981, but the index declined to one-third of peak levels by the late 1980s. The index increased during the early 1990s but has since declined once again. Spawning stock biomass (SSB) peaked at 2,100 mt in 1990, and has been variable since then. SSB in 2007 was 1,922 mt, which is only 25% of B MSY (7,792 mt) (Fig. 14). Estimated fishing mortality (F 2007 ) was 0.414, which was 1.7 times that of F MSY (0.24) (NEFSC 2008). Currently, the stock is overfished and overfishing is occurring (NEFSC 2008). 21

22 Figure 13. Commercial landings and discards for CC yellowtail flounder (NEFSC 2008). Figure 14. Trends in survey biomass for CC/GOM yellowtail flounder (Figure from NMFS 2010). Georges Bank yellowtail flounder stock The most recent assessment for GB yellowtail flounder was conducted in 2007 as part of the GARM III Assessment (NEFSC 2008). U.S. landings of GB yellowtail flounder have been variable (Fig. 15). Landings peaked in the early 1970s, but since 1985 have been less than 4,000 mt per year. Severe fishing restrictions (including a year-round closure of a large portion of GB) in 1995 caused landings to drop to 300 mt. From , the GB yellowtail flounder landings ranged between 800 mt 3,000 mt, similar to the CC/GOM stock. GB yellowtail 22

23 flounder landings peaked in 2004 at 5,837 mt; however, that same year CC/GOM landings plummeted to less than 100 mt. GB yellowtail flounder landings have remained in decline since 2004, with landings decreasing to 1,061 mt in GB (NEFSC 2008). Fishing mortality of fully-recruited ages was extremely high from 1973 to 1994, but steadily decreased from 2.3 (85% exploitation rate) in 1994 to less than 0.2 (16% exploitation rate) in In 2007, fishing mortality was 0.289, which is 114% of F MSY (0.254), meaning that overfishing was occurring. Spawning stock biomass (SSB) fluctuated at levels less than 5,000 mt from 1989 to 1995, and then steadily increased to 10,000 mt in 2003 (Fig. 16). SSB declined to about 4,000 mt by 2006, but rose again to 9,526 mt in 2007 (NEFSC 2008). This current SSB 2007 estimate is only 22% of SSB MSY. The population age structure has improved somewhat in recent years, but there are still fewer fish in the oldest age classes as estimated from catch and survey data (DFO 2003). More recently, the second quarter 2010 NMFS Status of U.S. Fisheries report concluded that the GB yellowtail flounder biomass is 49% of SSB MSY, the stock is overfished, but overfishing is not occurring (NMFS 2010). Given that the stock is overfished, overfishing is not occurring, and short-term biomass trends are variable Seafood Watch considers the GB yellowtail flounder stock to be a critical conservation concern. Figure 15. Catch of GB yellowtail flounder (Figure from NEFSC 2008). 23

24 Figure 16. Trends in survey biomass of GB yellowtail flounder (Figure from NEFSC 2008). Windowpane flounder There are two distinct windowpane flounder stocks in the Atlantic: Gulf of Maine/Georges Bank (GOM/GB); and Southern New England/Mid Atlantic Basin (SNE/MAB). Since the early 1990s, over 70% of the total windowpane flounder landings have been from the GOM/GB area (Hendrickson 2000). Southern New England/Mid Atlantic Basin windowpane flounder stock The SNE/MAB windowpane stock has never been formally assessed; however, index-based assessments have been conducted at GARM meetings. This last index-based assessment was conducted in 2007 as part of the GARM III Assessment (NEFSC 2008). Landings declined rapidly from , from a peak of 2,065 mt to a record low of 120 mt, respectively. From , landings stabilized at the lowest levels observed in the time series, ranging between 100 mt and 200 mt. Between , landings were at the lowest levels on record, ranging from 39 mt to 85 mt. Landings in 2007 totaled 81 mt (NEFSC 2008). The relative F 2007 value of 1.85 was 126% of FMSY (1.47); therefore, overfishing is occurring. The 2007 relative biomass index of 0.19 kg per tow was 56% that of BMSY (0.34 kg per tow), which illustrates that the stock is rebuilding from its previously overfished condition (NEFSC 2008). However, exploitation rates are based only on landings. Since 1994, most of the catch has been comprised of discards (NEFSC 2008), and if unaccounted discarding is substantial, then the average exploitation rate is an underestimate (NEFSC 2002a). The most recent GARM III report states that underestimation of total discards results from vessels fishing in state waters without a Federal fishing permit are unavailable (NEFSC 2008). Such underestimation of total landings, coupled with limited information on age structure leads to a moderate degree of uncertainty in the status of the stock. According to Seafood Watch criteria, stock status is considered poor because the stock is subject to overfishing but is not currently overfished. 24

25 Gulf of Maine/Georges Bank windowpane flounder stock During most years, the GOM/GB stock has comprised a higher proportion of total landings than the SNE/MAB stock. Commercial landings of GOM-GB were highest between 1985 and 1993 (1,212 2,862 mt). Peak landings during this time most likely reflected an expansion of the fishery to offshore areas, as well as the targeting of windowpane flounder as an alternative to depleted groundfish stocks. Since 1994, however, landings have occurred as a result of bycatch, and GOM/GB landings declined from 773 mt in 1996 to record lows of less than 50 mt/year from In 2007, landings totaled 119 mt (NEFSC 2008). Biological reference points for GOM/GB windowpane flounder were derived from survey-based proxies of biomass and exploitation rates and are based on an ASPIC-based MSY estimate of 1,000 mt. Current biological reference points from the GARM III assessment are as follows: B 2007 = 0.24 kg/tow, which represents 17% of B MSY (1.40 kg/tow); and F 2007 = 1.96 kg/tow, which is 392% of F MSY (0.50 kg/tow) (NEFSC 2008). Based on these reference points, it was declared that the stock is overfished and that overfishing is occurring (NEFSC 2008). Discarding is not included in fishing mortality estimates, and may represent a sizable fraction of the multispecies catches given recent groundfish retention restrictions (NEFSC 2002a). Like the SNE/MA, the most recent GARM III report states underestimation of total discards, and limited to no information on age structure for this stock (NEFSC 2008), resulting in a moderate degree of uncertainty in the status of the stock. According to Seafood Watch criteria, the status of this stock is a critical conservation concern because the stock is overfished and experiencing overfishing. Gulf of Maine/Georges Bank American plaice American plaice has become increasingly targeted as other commercially important species have declined. Landings averaged about 2,300 mt in the 1970s, increased to an average of 13,000 mt in the early 1980s, and are currently average between 3,000 7,000 mt per year (Fig. 17). In the 1960s 1970s the majority of U.S. landings were from deep water grounds of Georges Bank. Currently GOM landings exceed those of GB. Otter trawls account for over 95% of landings (Mayo and Terceiro 2005). The most recent assessment for American plaice determined SSB 2007 to be 11,106 mt. This represented 51% of B MSY (21,940 mt). Fishing mortality (F 2007 ) was 0.09, or 47% of F MSY (0.19) (NEFSC 2008). SSB has a long-term decreasing trend but an increasing short-term trend (Fig. 17) (NEFSC 2008). Current assessments indicate that the stock is not overfished and overfishing is not occurring, as the stock is rebuilding (NEFSC 2008). There was no information available to comment on age structure, but given the level of fishing pressure it is reasonable to assume some truncation towards younger age classes has occurred. According to Seafood Watch criteria, stock status is considered to be a moderate conservation concern because biomass is 51% of SSB MSY and overfishing is not occurring. However, American plaice is caught in a multi-species fishery where many stocks are in poor or critical condition, and is closely associated with witch flounder (Gabriel 1992), which has a critical stock status. Directed fishing for American plaice also inevitably increases the already unsustainable fishing pressure on associated depressed stocks such as witch flounder. Thus, in adherence to the precautionary principle, American plaice stock status is ranked poor to account for the poor or critical stock status of closely associated stocks in the same fishery. 25

26 Figure 17. Trends spawning for GOM/GB American plaice, : A) Total commercial catch and fishing mortality (F); and B) recruitment and stock biomass (SSB) (Figure from NEFSC 2008). Atlantic halibut Whereas most Atlantic flounder stocks have been fished in just the last century, Atlantic halibut have been exploited commercially since the 1830s (NEFSC 2002a). Annual landings averaged 663 mt from and declined to an average of 144 mt from From , landings averaged 91 mt/yr (Fig. 18). In 2007, landings totaled 52 mt 22mt, (42%) of which were landed by US fishermen and 30 mt (58%) were landed by Canadian fishermen (NEFSC 2008). In 2007, fishing mortality was 0.065, or 93% of F MSY (NEFSC 2008). Previous research assessments conducted by GARM 2005 declared that the Atlantic halibut stock was overfished, and at that time it was unknown whether overfishing was occurring (Brodziak and Col 2005; NEFSC 2008). It should be noted that uncertainty in time series stock biomass estimates may be high, due to changes in doors, nets and vessels throughout the survey period ( ) (NEFSC 2008). The GOM/GB stock was last assessed in 2007 (GARM 2007). This assessment indicated that the Atlantic halibut stock is overfished but not subject to overfishing (NEFSC 2008; NMFS 2010). In 2007, SSB was 1,300 mt, equal to 2.7% of B MSY (49,000 mt). The long and short-term trends in biomass are variable (Fig. 19). According to Seafood Watch, the Atlantic halibut stock is considered to be of critical conservation concern because the stock is overfished and the trend in abundance is variable. 26

27 Figure 18. Atlantic halibut total catch (mt) from the Gulf of Maine-Georges Bank region during (Figure from NEFSC 2008). Figure 19. Biomass trend for Atlantic halibut, (Figure from NEFSC 2008). Note: the bottom red line is the best fit line. 27

28 Table 2. Stock status and trends for U.S. Atlantic flatfishes. Fishing mortality (F) and biomass (B) data are as of 2007, unless otherwise noted (NEFSC 2008). A ratio of F 2007 /F msy > 1 indicates overfishing is occurring, while a ratio of B 2007 /B msy > 1 indicates the stock is not overfished (NOTE: a ratio of B 2007 /B msy < 1 does not necessarily indicate an overfished stock). Stock Summer flounder Winter (GOM) Classification Status Not OFD; No OFG Unknown B 2007 /B msy (% Biomass rebuilding needed) B 2008/ B msy = 0.77 Unknown but likely below ½ Bmsy F 2007 /F msy (%F reduction required) 0.81 Winter (GB) OFD & OFG Winter (SNE/MA) Witch flounder Yellowtail (SNE/MA) Yellowtail (CC/GOM) Yellowtail (GB) Windowpane (SNE/MAB) Windowpane (GOM/GB) American Plaice Atlantic halibut OFD & OFG OFD & OFG OFD & OFG OFD & OFG OFD; No OFG Not OFD (rebuilding); OFG Unknown Abundance Trends Increasing since 1991 Long-term decreasing; short-term variable Long and short-term variable Long and short-term variable Long and short-term decreasing Long-term decreasing; short-term flat Long and short-term variable Increasing since 2005 Age/Size/Sex Distributions Truncated but improving Truncated size structure Degree of Uncertainty Low High SFW Rank Moderate Poor No clear data Low Critical Truncated but improving Truncated age structure Truncated age structure Truncated age structure Truncated age structure Low Low Low Low Low Critical Critical Critical Critical Critical Unknown Unknown Moderate Poor OFD & OFG Unknown Unknown Moderate Critical Not OFD (rebuilding); No OFG OFD; No OFG OFD = Overfished, OFG = Overfishing (Terceiro 2009) Long-term decline; short-term increase Long and short-term variable Unknown Low Poor Unknown High Critical 28

29 Synthesis Of the 12 flounder stocks mentioned here, 8 stocks are overfished and 7 stocks are experiencing overfishing (6 of these are overfished). As stocks are depleted in one area, effort is re-directed to new areas. This repetitive phenomenon is indicative of an overcapitalized fleet fishing on an ever-decreasing resource. Although American plaice is not overfished and overfishing is not occurring, this species is caught in a multi-species fishery where most stocks are in poor or critical condition, and is therefore ranked poor for stock status. Stock status of winter flounder (GOM) and windowpane flounder (SNE/MA) are also ranked poor, while winter flounder (GM and SNE/MA), witch flounder, windowpane flounder (GOM/GB), Atlantic halibut and yellowtail flounder have critical stock status because these stocks are overfished and overfishing is occurring. Summer flounder is moderately below target stock levels but is not overfished and overfishing is not occurring, and summer flounder is not closely associated with other flatfish that have depleted stocks. Therefore, summer flounder stocks are ranked moderate. Conservation Concern: Status of Stocks Moderate Summer flounder Poor Critical American plaice Winter (GOM) Windowpane (SNE/MA) Winter (GB) Winter (SNE/MA) Witch flounder Yellowtail (SNE/MA) Yellowtail (CC/GOM) Yellowtail (GB) Windowpane (GOM/GB) Atlantic halibut Criterion 3: Nature of Bycatch Seafood Watch defines sustainable wild-caught seafood as marine life captured using fishing techniques that successfully minimize the catch of unwanted and/or unmarketable species (i.e., bycatch). Bycatch is defined as species that are caught but subsequently discarded (injured or dead) for any reason. Bycatch does not include incidental catch (non-targeted catch) if it is utilized, accounted for and/or managed in some way. Due to the mixed species nature of the Atlantic groundfish fishery, as well as the gear type used (bottom/otter trawl), bycatch and subsequent discarding of unmarketable or otherwise illegal (e.g., undersized) species occurs frequently. In addition, trip limits, a management tool used to regulate catch, forces otherwise market-worthy fish to be discarded. Managers have mitigated this somewhat by increasing the allowable mesh size in the trawl gear, reducing the catch of 29

30 smaller-sized fishes. There have been a small number of observed interactions with marine mammals and sea turtles in the trawl fisheries. In 2003, Fishery Observers on 590 trawling (bottom otter) trips recorded a total of 21 interactions with marine mammals, and 4 interactions with sea turtles (NMFS 2004). According to the Multispecies Groundfish FMP, trawlers are required to report all discards via logbooks and use bycatch reduction devices (BRDs) such as Nordmore grate and mesh panels (NOAA 2002b). Observer coverage is only about 5%, however, thus numbers of total discards may be underestimated. Nature of Bycatch Rank: Low Moderate High Critical Criterion 4: Effect of Fishing Practices on Habitats and Ecosystems Habitat Effects Most of the flatfishes discussed in this report are captured with various types of demersal trawl gear (mainly otter trawls, Fig. 20) tailored to the habitats of target species or species assemblages. Trawling impacts sea-floor communities by scraping the ocean bottom causing 1) sediment re-suspension (turbidity) and smoothing, 2) removal and/or damage to non-target species, and 3) destruction of three-dimensional habitat (biotic and abiotic; Auster and Langton 1999). The degree of impact is determined by many factors, most notably 1) the type and weight of gear used; 2) the resilience of the seabed; and 3) the amount and frequency of the disturbance. Although studied to a lesser extent than otter trawls, mid-water trawls may also reduce available habitat by disturbing aggregations of gelatinous zooplankton and other floating matter, which has been shown to provide pelagic habitat for fish aggregations (Auster et al. 1992, Brodeur in press in (NEFMC 1998)). Several studies on the effects of bottom trawling have focused on the heavily trawled fishing grounds in the northwest Atlantic (Collie et al. 1997; Collie et al. 2000). Prena et al. (1999), for example, conducted an experimental trawl study on the Grand Banks off Newfoundland and reported that otter trawling on a sandy bottom ecosystem can produce detectable changes on both benthic habitat and communities, in particular a significant reduction in the biomass of large epibenthic fauna. At a workshop to assess the effects of fishing gear on marine habitats off the northeastern U.S., experts concluded that the greatest impacts from otter trawls occur in low and high energy gravel habitats and in hard clay outcroppings (NOAA 2002b); p 24). Based on the results of this and other studies, it is apparent that otter/bottom trawling may alter the surrounding ecosystem, as well as reduce survival of the target species, by reducing or altering available habitat and food resources. 30

31 Figure 20. General diagram of an otter trawl, courtesy Matt Squillante, Monterey Bay Aquarium. Bottom trawl disturbance of the seabed is mainly a function of bottom type (rock, sand, mud, etc.) and gear type (dredge, beam, otter trawl, etc.). Some types of trawling gear cause less damage (i.e., otter trawls vs. scallop dredge) and some sediment types (and their associated ecosystems) are more resilient to disturbances caused by trawling. In a review of fishing effects, Collie et al. (2000) found that fauna associated with sandy (coarser) sediments were less affected by disturbance than those in soft, muddy (biogenic) sediments. Recovery rate appears to be slower in muddy and structurally complex habitats, while mobile sandy sediment communities can withstand 2-3 trawl passes per year without significant (adverse) change (Collie et al. 2000). The bathymetry of the Atlantic continental shelf, and habitat preferences of flatfish species, is such that groundfish trawlers targeting flatfishes off the U.S. East Coast encounter both types of substrate (see Appendix I, Table 3). Otter trawling has been ranked as causing less disturbance to the sea floor than other types of trawling, such as inter-tidal and scallop dredging (Collie et al. 2000; NOAA 2002b), but it is probable that repetitive trawling in these areas causes significant, and possibly adverse change to seabed ecosystems along the U.S. East Coast. Table 3. Reported habitat type and depth preferences of flatfish species of U.S. or Canada East Coast. SPECIES HABITAT PREFERENCE REFERENCES Hard, sandy or muddy substrate; (Packer et al. 1999; Froese and Pauly shallow coastal (summer), outer 2003) continental shelf <150m (winter) Summer flounder Winter flounder Witch flounder Yellowtail flounder Windowpane flounder American plaice Atlantic halibut Juveniles: muddy substrates; inshore: soft (muddy sand) bottom to 92m, offshore: hard bottom Soft, mud/clay/silt/muddy sand bottoms <1,500m Sand/sandy-mud sediments, some gravel, m m but common < 55m; sand/mud 90-1,400 m; fine, sticky/gritty mixture of mud and sand Sand/gravel/clay bottom, m (to 1,000 m) (Pereira et al. 1999; Collete and Klein- MacPhee 2002) (Cargnelli et al. 1999b; Collete and Klein-MacPhee 2002; Froese and Pauly 2003) (Johnson et al. 1999; Collete and Klein- MacPhee 2002; Froese and Pauly 2003) (Collete and Klein-MacPhee 2002) (O'Brien 2000; Collete and Klein- MacPhee 2002) (Cargnelli et al. 1999a; Collete and Klein-MacPhee 2002) 31

32 Ecosystem Effects The fishing grounds of the Gulf of Maine, Georges Bank, and the continental shelf off New England represent one of the most productive oceanic ecosystems in the world. Tidal cycles and strong current flows lead to an extremely productive clockwise gyre in which a diverse array of life flourishes. Analyses of food web structure show that this area is rich in species diversity and abundance, and has a high degree of complexity and connectivity (Brodziak and Link 2002). Consequently, heavy fishing pressure over the last few centuries has resulted in a notable shift from a largely benthic fish community towards a largely pelagic fish community (Fogarty and Murawski 1998; Brodziak and Link 2002). It is extremely difficult to quantify the effects of this shift, but certain outcomes have been theorized, such as changes in predator-prey interactions and species survival rates, and decreases in overall productivity and perturbation of food web dynamics (Brodziak and Link 2002). One example is the increased predation on groundfish larvae by small pelagic species such as mackerel and herring, and a shift in the dominant fish predator from cod to spiny dogfish during the 1980s (Brodziak and Link 2002). In addition to fishing impacts, natural and anthropogenic environmental impacts (i.e., temperature shifts, such as the North Atlantic Oscillation) may also be resulting in changes to the ecosystem, and separating the effects of fishing and the effects of environmental changes may be close to impossible. Synthesis Based on the published literature noting the adverse effects of trawling on the various habitat types where flounders are found, as well as the significant amount of fishing effort along the continental shelf over the last 50 years, it is reasonable to assume that trawling for flatfishes has significantly altered or damaged a large portion of the seabed and the ecosystem. The degree of recovery from these actions is largely unknown and the effects of these fishing practices on habitats and ecosystems is ranked severe. Effect of Fishing Practices Rank: Benign Moderate Severe Critical Criterion 5: Effectiveness of the Management Regime The U.S. Atlantic Groundfish fishery was largely unregulated until the 1950s, when the newly (1949) formed International Commission for Northwest Atlantic Fisheries (ICNAF) began to set certain restrictions in response to concerns about wasteful bycatch and declines in groundfish abundance (Fogarty and Murawski 1998). ICNAF managers used a harvest strategy involving trip limits or total allowable catch (TAC) and annual quotas, but these regulations were largely disregarded by fishermen and landings were consistently higher than target levels. Fisheries independent surveys were implemented in 1963, and the first formal stock assessments of cod, haddock, and yellowtail flounder were conducted in 1971 (NRC 1998). In 1977, the New England Fishery Management Council (NEFMC) gained control over the fishery (as mandated by the MFCM Act, passed in 1976). In 1982 the NEFMC implemented the Multispecies 32

33 Groundfish FMP, which contained a suite of indirect effort control measures such as minimum mesh size and fish size restrictions, and seasonal area closures (NRC 1998). Despite these attempts at regulating the fishery, exploitation rates could not be sustained, and populations declined severely in the late 1980s and early 1990s. In response to stock collapse, more restrictive measures were put into place, severely affecting coastal fishing communities. In 1994, a moratorium on groundfish fishing (all mobile gears) was implemented for a large area of Georges Bank and southern New England (Fogarty and Murawski 1998). As discussed above, stock assessments indicate that many flounder stocks have not recovered. The fishery is currently facing stricter measures to allow rebuilding (Amendment 13). Summer flounder is managed jointly by federal and state governments under the Summer Flounder, Scup and Black Sea Bass joint ASMFC/MAFMC FMP as a unit stock from North Carolina to Maine (Terceiro 2003). Subsequent amendments to the FMP implemented several major regulatory provisions, including annual commercial quotas, recreational harvest limits, a new commercial vessel permit moratorium, minimum fish size and mesh size for trawls, and a recreational fishery possession limit. Amendment 12 to the FMP, approved in 1999, revised the overfishing definition for summer flounder. Table 6. Summary of management regulations for the Multispecies groundfish complex, of which flatfishes are included. Jurisdiction and Agencies State & federal TAC Yes, variable by species and year Size Limits Variable by species Trip Limits Days-at- Sea (DAS) limits Gear Restrictions Yes (mesh size, roller gear size) Observer Program Yes, ~ 5% coverage (Amend. 13 will increase coverage) Closed Seasons/Areas Yes (GB seasonally) Managers assess stock abundance of groundfish species at regular intervals, analyzing both fisheries dependent (catch records, effort, etc.) and fisheries independent (NMFS trawl surveys, tagging studies, etc.) data. Age based data is available for the most commercially important species, and is used to model stock structure, recruitment capability, and overall biomass. Groundfish regulations included minimum cod-end mesh size, minimum fish size, seasonal area closures, mandatory reporting, trip limits and annual quotas (NEFSC 2003a). By law (MSFCMA/SFA 1996), the Fisheries Councils are required to prevent, mitigate, or minimize any adverse effect from fishing, to the extent practicable, if there is evidence that a fishing practice is having an identifiable adverse effect on Essential Fish Habitat (EFH; NEFMC 1998). To conform with this requirement, the NEFMC has closed certain areas entirely to fishing and limited fishing effort to 88 days-at-sea (DAS) per year for each groundfish permit holder (NEFMC 1998); p.188). The system of closed areas on Georges Bank protects approximately 6,500 square nautical miles year-round by completely closing this area to fishing. In the Gulf of Maine, approximately 13,000 square nautical miles of habitat are protected during temporary closures, with an additional 1,200 square nautical miles closed year-round (NEFMC 1998). In addition to these measures, the council, through Amendment 9 to the Groundfish FMP, prohibited the use of street-sweeper trawl gear, which is thought to be highly efficient 33

34 (so as to nullify DAS protections) and whose entire footrope length is in contact with the bottom (NEFMC 1998). In May 2000, the Conservation Law Foundation (CLF) filed a lawsuit against NMFS charging that approved groundfish catch levels were too high (see Appendix II) and thus violated federal law by risking further depletion of New England groundfish populations. In December 2001, a federal district court judge upheld CLF's allegations that NMFS did not act to prevent overfishing and decrease bycatch in the New England groundfish fishery. The court found that NMFS was violating the federal Sustainable Fisheries Act of 1996 by failing to obey its own regulation that mandates rebuilding fish populations and prohibits the continued overfishing of cod and other groundfish off the coast of New England. In response to a 2002 court order, the New England Fishery Management Council is updating its groundfish management plan (Amendment 13), which is set to be implemented in May Synthesis, analysis and evaluation of relevant factors Managers of Northeastern Groundfish resources assess stocks on a timely basis (annually or semi-annually) and use both fisheries dependent and independent data to determine stock status and fishing levels. Managers require specific mesh sizes and gear types to reduce wasteful discard, as well as implement seasonal and permanent closure areas to reduce trawling impacts. Management has not, however, prevented the extreme declines of many commercially important flatfishes, and is therefore considered only moderately effective. Effectiveness of Management Rank: Highly Effective Moderately Effective Ineffective Critical Taken from: 34

35 Overall Evaluation and Seafood Recommendation Most of the flatfishes evaluated in this report are moderately long-lived (10-30 yrs) and fairly quick to mature (< 5yrs), and are thus thought to be relatively resistant to fishing pressure. Stock status varies by species and fishing area, but currently the majority of flounder stocks are overfished, with fishing mortality exceeding targets (overfishing). As a result, most flounder stocks have poor or critical stock status. An exception is summer flounder, which is rebuilding and has moderate stock status. Trawling is thought to disturb sea floor habitat depending upon gear components and bottom type resiliency, and is considered severely detrimental to habitats and ecosystems. By its nature, trawling is also indiscriminate in terms of species caught, and along with targeted catch trawl nets take unmarketable or undersized species that are fatally discarded, adding to the overall fishing mortality of many groundfish species. Heavy fishing pressure of groundfish stocks has also been implicated in an ecosystem shift towards increased pelagic biomass in the northwest Atlantic. Managers of groundfish stocks have attempted to mitigate these issues by closing over 25,000 square miles of ecologically sensitive habitat to trawling, including discard mortality in their stock analyses, and regulating gear makeup. In addition, managers actively observe stock abundance patterns and have implemented several regulations over the years in an attempt to maintain stock productivity. The management regime has not, however, prevented significant declines of many flounder species, and is therefore considered moderately effective. Due to the poor to critical status of the stocks and the severe habitat/ecosystem impacts, winter flounder, witch flounder, yellowtail flounder, windowpane flounder, American plaice, and Atlantic halibut are recommended as Avoid. Due to severe habitat/ecosystem impacts, but moderate stock status, bycatch and management effectiveness, and low inherent vulnerability, summer flounder is recommended as a Good Alternative. 35

36 Table of Sustainability Ranks Conservation Concern Sustainability Criteria Low Moderate High Critical Inherent Vulnerability Status of Stocks Nature of Bycatch Habitat Effects Management Effectiveness Overall Seafood Recommendation: Summer flounder American plaice, Winter (GOM), Windowpane (SNE/MA) Winter (GB), Winter (SNE/MA), Witch flounder, Yellowtail (SNE/MA), Yellowtail (CC/GOM), Yellowtail (GB), Windowpane (GOM/GB), Atlantic halibut Seafood Watch Recommendation Good Alternative Summer flounder Avoid American plaice, winter flounder, witch flounder, yellowtail, windowpane, Atlantic halibut Acknowledgements The Seafood Watch Program would like to thank Dr. John Brodziak and Dr. Mark Terceiro of the National Marine Fisheries Service, Northeast Fisheries Science Center, for reviewing this document. Scientific review does not constitute an endorsement of Seafood Watch on the part of the reviewing scientists. The Seafood Watch staff is solely responsible for the conclusions reached in this report. 36

37 References ASMFC Review of the Atlantic States Marine Fisheries Commission s Interstate Fishery Management Plan for Winter Flounder (Pseudopleuronectes americanus). FMP Review Accessed August 26, erflounderfmpreview08.pdf Auster, P. J. and R. W. Langton The Effects of Fishing on Fish Hbitat. American Fisheries Society Symposium 22: Brodziak, J. K. T. and J. Link Ecosystem-based fishery management: What is it and how can we do it? Bulletin of Marine Science 70(2): Brodziak, J.K.T. and Col L Atlantic halibut. In NEFSC, Assessment of 19 Northeast groundfish stocks through Groundfish Assessment Review Meeting (2005 GARM) Woods Hole, MA. August NEFSC Ref Doc ; 499 p. Available at: Cadrin, S Yellowtail Flounder. Status of Fisheries Resources off Northeastern US. NOAA/NEFSC. Cargnelli, L. M., S. J. Griesbach, P. L. Berrien, W. W. Morse and D. L. Johnson.1999a. Atlantic Halibut, Hippoglossus hippoglossus, Life History and Habitat Characteristics. D. B. Packer. NOAA/NMFS/NEFSC. 26pp. Cargnelli, L. M., S. J. Griesbach, P. L. Berrien, W. W. Morse and D. L. Johnson.1999b. Essential Fish Habitat Source Document: Witch Flounder, Glyptocephalus cynoglossus, Life History and Habitat Characteristics. D. B. Packer. NOAA/NMFS/NEFSC. 38pp. Collete, B. and G. Klein-MacPhee, Eds Bigelow & Schroeder's Fishes of the Gulf of Maine. Washington, DC, Smithsonian Institution. Collie, J. S., G. A. Escanero and P. C. Valentine Effects of bottom fishing on the benthic megafauna of Georges Bank. Marine Ecology Progress Series 155: Collie, J. S., S. J. Hall, M. J. Kaiser and I. R. Poiner A quantitative analysis of fishing impacts on shelf-sea benthos. Journal of Animal Ecology 69: DFO Georges Bank Yellowtail Flounder, Stock Status Report 2003/042. Department of Fisheries and Oceans Canada Fogarty, M. J. and S. A. Murawski Large-scale disturbance and the structure of marine systems: Fishery impacts on Georges Bank. Ecological Applications 8 (Supplement)(1): S6-S22. Froese, R. and D. Pauly FishBase. World Wide Web electronic publication. November

38 Gabriel, W. L Persistence of Demersal Fish Assemblages Between Cape Hatteras and Nova Scotia, Northwest Atlantic. Journal of Northwest Atlantic Fisheries Science 14: Hendrickson, L Windowpane Flounder: Summary of Landings and Stock Status. Northeast Fisheries Science Center, NOAA.: 6 p. Johnson, D. L., W. W. Morse, P. L. Berrien and J. J. Vitaliano Essential Fish Habitat Source Document: Yellowtail Flounder, Limanda ferruginea, Life History and Habitat Characteristics. NOAA Tech Memo NMFS-NE-140. NOAA/NMFS/NEFSC: Mayo, R. K. and M. Terceiro Groundfish Assessment Review Meeting (2005 GARM), Northeast Fisheries Science Center, Woods Hole Massachusetts, August Musick, J. A. and L. P. Mercer Seasonal Distribution of Black Sea Bass, Centropristis striata, in the Mid-Atlantic Bight with Comments on the Ecology and Fisheries of the Species. Transactions of the American Fisheries Society 106: National Marine Fisheries Service (NMFS) nd quarter 2010 Status of U.S. Fisheries. cy_q2_2010.pdf Northeast Fishery Management Council (NEFMC) Essential Fish Habitat. New England Fishery Management Council/NOAA/NMFS/NEFSC. Northeast Fisheries Science Center (NEFSC). 2002a. Assessment of 20 Northeast Groundfish Stocks through 2001, A Report of the Groundfish Assessment Review Meeting (GARM). Ref Doc Northeast Fisheries Science Center (NEFSC). Woods Hole, MA. NEFSC. 2002b. Report of the 34th Northeast Regional Stock Assessment Workshop (34th SAW), Stock Assessment Review Committee (SARC) Consensus Summary of Assessments. NEFSC Ref. Doc NEFSC. 2003a. Report of the 36th Northeast Regional Stock Assessment Workshop (36th SAW), Stock Assessment Review Committee (SARC) Consensus Summary of Assessments. NEFSC Ref. Doc NEFSC. 2003b. Report of the 37th Northeast Regional Stock Assessment Workshop (37th SAW), Stock Assessment Review Committee (SARC) Consensus Summary of Assessments. NEFSC Ref. Doc 03-17: 52pp. NEFSC Assessment of 19 northeast groundfish stocks through 2004: Groundfish Assessment Review Meeting (2005 GARM), Northeast Fisheries Science Center. Woods 38

39 Hold, Massachusetts. August 15-19, Mayo RK, Terceiro M, eds. NEFSC Ref Doc ; 448 p. + Appendices. NEFSC Assessment of 19 Northeast Groundfish Stocks through 2007: Report of the 3rd Groundfish Assessment Review Meeting (GARM III), Northeast Fisheries Science Center, Woods Hole, Massachusetts, August 4-8, US Dep Commer, NOAA FIsheries, Northeast Fish Sci Cent Ref Doc ; 884 p + xvii. Nelson, J. S Fishes of the World. 3rd edition. New York, NY, John Wiley & Sons, Inc. 600pp. Nitschke, P., R. Brown and L. Hendrickson Winter Flounder: Status of the Fishery Resources off the Northeastern United States. NOAA/NEFSC. NMFS Fisheries Statistics & Economics Database. website. National Marine Fisheries Service; Department of Commerce NMFS Yellowtail flounder (Limanda ferruginea). National Marine Fisheries Service; Department of Commerce. Accessed August 26, NMFS Incidental Take Report. Northeast Fisheries Observer Program, NOAA/NEFSC NOAA. 2002a. Status of US Fisheries in NOAA Fisheries, Department of Commerce. NOAA. 2002b. Workshop on the Effects of Fishing Gear on Marine Habitats off the Northeastern United States, October 23-25, Northeast Region Essential Fish Habitat Steering Committee: 86 pp. Boston, Massachusetts. NRC Review of Northeast Fishery Stock Assessments. National Academy Press: 127pp. National Research Council, Washington D.C. O Boyle, R Panel Summary Report of the Groundfish Assessment Review Meeting (GARM III), Part 3: Biological Reference Points. Northeast Fisheries Science Center; NOAA. O'Brien, L American Plaice: Status of Fishery Resources off the Northeastern United States. Northeast Fisheries Science Center; NOAA. Packer, D. B., S. J. Griesbach, P. L. Berrien, C. A. Zetlin, D. L. Johnson and W. W. Morse Essential Fish Habitat Source Document: Summer Flounder, Paralichthys dentatus, Life History and Habitat Characteristics. NOAA Tech Memo NMFS-NE

40 NOAA/NMFS/NEFSC: 98pp. Pereira, J. J., R. Goldberg, J. J. Ziskowski, P. L. Berrien, W. W. Morse and D. L. Johnson Essential Fish Habitat Source Document: Winter Flounder, Pseudopleuronectes americanus, Life History and Habitat Characteristics. NOAA Tech Memo NMFS-NE NOAA/NMFS/NEFSC: 48 pp. SAW st Northeast Regional Stock Assessment Workshop (41st SAW). 41st SAW assessment summary report. U.S. Dep. Commer., Northeast Fish. Sci. Cent. Ref. Doc ; 36 p. Available from: National Marine Fisheries Service, 166 Water Street, Woods Hole, MA SAW 47, th Northeast Regional Stock Assessment Workshop (47th SAW) Assessment Report. US Dept Commer, Northeast Fish Sci Cent Ref Doc a; 335 p. Terceiro, M Stock Assessment for summer flounder for Northeast Fish. Sci. Cent. Ref. Doc.03-09; 179 p. Available from: National Marine Fisheries Service, 166 Water St., Woods Hole, MA Terceiro M Stock Assessment of Summer Flounder for NEFSC Ref Doc 09-17; 132 p. Wigley, S. E., J. K. T. Brodziak and L. Col Assessment of the Gulf of Maine and Georges Bank Witch Flounder Stock for NEFSC NOAA/NMFS/NEFSC: 194pp. Woods Hole, MA. 40

41 Appendix I. Geomorphology of the New England fishing grounds, from NEFSC (1998). Figure A1. Map showing distribution of sediments, Gulf of Maine, Georges Bank, and southern New England. Southern New England sediment distribution is similar to the Mid-Atlantic Basin region. 41

42 Appendix II. Figures from the Conservation Law Foundation s 2000 lawsuit alleging NMFS s failure to rebuild and protect some groundfish stocks. Figure A2a & A2b. Comparison of Mortality vs. Target (a) and Biomass vs. Target (b) for SNE/MA winter flounder. Courtesy CLF **. ** Source: data from NEFSC Draft 36th Northeast Regional Stock Assessment Review Committee, January estimates from NEFMC Groundfish PDT memo, March 31,

43 Figure A3a & A3b. Comparison of Mortality vs. Target (a) and Biomass vs. Target (b) for GOM/CC yellowtail flounder. Courtesy CLF. 43

44 Figure A4a & A4b. Comparison of Mortality vs. Target (a) and Biomass vs. Target (b) for American plaice. Courtesy CLF. 44