Seafood Watch Seafood Report

Southern Flounder (Paralichthys lethostigma)

Gulf of Mexico & South Atlantic Regions Final Report April 6, 2004

Melissa Mahoney Stevens Fisheries Research Analyst Monterey Bay Aquarium

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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 emailing [email protected]. 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.

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Seafood Watch® Southern Flounder Report April 6, 2004

Executive Summary Southern flounder is a coastal flatfish that supports US commercial and recreational fisheries along the coasts of the Gulf of Mexico (GOM) and Atlantic Ocean, mainly off North Carolina (NC). This species of flatfish is fast growing, short-lived (<10 years) and matures quickly (< 5yrs). Annual commercial landings are significantly higher in the Atlantic (3.5 million pounds in NC) than in the Gulf region (~ 300,000 pounds). In the GOM, the directed commercial fishery for flounders uses seines, hook and line, or gig, none of which have been shown to have significant bycatch or adversely affect habitat. On the Atlantic side pound nets, gillnets, and gigs are used to target southern flounder. Pound nets and gigs are very selective (low bycatch) and are thought to have minimal habitat impacts to estuarine areas where they are used. Deep-water large mesh gillnets in Pamlico Sound, NC, have been shown to cause strandings of protected sea turtles, but measures have been taken to reduce the amount of interactions. Stock status in the GOM is uncertain due to the lack of species-specific fisheries dependent and/or robust independent data. In the Atlantic inshore waters of North Carolina, southern flounder is considered overfished with overfishing occurring.

In the GOM, southern flounder is incidentally caught and retained from shrimp trawl operations. This fishery is of greater concern, as trawls have been shown to take excessive amounts of other fishes (mostly immature), invertebrates, and sea turtles respective to shrimp catch. Trawls are also thought to cause moderate alterations to sea bottom habitat in the Gulf. Individual states are responsible for management of southern flounder; interjurisdictional cooperation is achieved through the Gulf States Marine Fisheries Commission. Together these agencies regulate fishing pressure through fishing regulations such as bag limits (recreational) and permit qualifications (commercial). Management is moderately effective with respect to southern flounder stocks, as stock uncertainties need to be addressed, and in North Carolina, where a stock assessment and fishery management plan are currently being developed for a mature fishery.

Table of Ranks

Sustainability Concern: Concern: Concern: Concern: Criteria Low Moderate High CRITICAL Inherently √ Vulnerability Status of √ (GOM) √ (NC) Stocks Nature of Bycatch √ (GOM - √ (Pound nets, √ (Deep-water incidental take

gig) gillnets, NC) from shrimp trawl) Habitat √ (Directed √ (shrimp trawl) Effects fishery) Management √ Effectiveness

Overall Seafood Rank:

Avoid - Atlantic (NC)

Good Alternative – GOM

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Introduction The southern flounder (Paralichthys lethostigma) is a large, euryhaline1 flatfish of in the family Bothidae (Hoese and Moore 1998). It inhabits coastal areas around the Gulf of Mexico (GOM) and southern US Atlantic coasts from North Carolina to Florida (particularly off North Carolina), and supports valuable commercial and recreational fisheries in those areas. It is closely related and often confused with two other species, summer flounder (P. dentatus) and gulf flounder (P. albigutta). One distinguishing factor is the absence of ocellated spots on the dorsal surface (Hoese and Moore 1998).

The distribution of southern flounder appears to be substrate-related, as they are mainly found on silt/mud substrate (GSMFC 2000; FMRI 2003). Southern flounder inhabit the coastal waters of the GOM to the Caloosahatchee River, in Florida, and are present in the Atlantic Ocean from the Loxahatchee River, Florida up to Albemarle Sound, North Carolina (Fig. 1; Ginsburg 1952; FMRI 2003). Individuals can tolerate wide temperature (~ 5-35˚C) and salinity ranges (~ 0.0- 60.0‰), inhabiting both brackish/freshwater and saltwater environs. Individuals reside in bays and estuaries throughout the spring and summer, migrating offshore in the fall to spawn. The fishery is most active during this period when fish are moving2.

Figure 1. Distribution of gulf and southern flounder in the southeastern US (GSMFC 2000).

Availability of Science There is a reasonable amount of information pertaining to life history of southern flounder. In the GOM, species-specific fisheries data is extremely limited, which hampers realistic conclusions reached in stock assessments. In the Atlantic, the largest fishery for this species (by

1 Able to tolerate fresh and salt water environs. 2 Carter Watterson. Personal Communication. North Carolina Division of Marine Fisheries. 3441 Arendell St, Morehead City, NC 28557.

4 Seafood Watch® Southern Flounder Report April 6, 2004 volume and value) is off North Carolina, so this evaluation focuses entirely on that state. There is no information related to fisheries or stocks in other Atlantic states. There appears to be sufficient information to assess stocks off NC, although the data series is limited to 12 years (1991-2002). There is no species-specific trade data for southern flounder, so nothing is known about import and export activity.

Market Availability

Common/Market names The southern flounder is often referred to as southern large flounder, mud flounder, halibut, plie (Louisiana French), southern fluke, and doormat (Reagan and Wingo 1985; Hoese and Moore 1998). When used for sushi or sashimi, flounders are commonly sold as hirame.

Seasonal Availability Due to their fall migrations, flounder landings peak between the months of August and November, dropping off significantly in late winter/early spring (GSMFC 2000).

Product forms Most GOM states require that southern flounder be landed whole/round form. Consequently, a market survey conducted in 1996 showed that 66% of flounders were sold whole, and 80% of those were sold fresh (GSMFC 2000). The remainder was filleted and sold either fresh or frozen, or processed into value-added products. In North Carolina, southern flounder are sold whole or processed into fillets, which are marketed in both stores and restaurants. Unfortunately, most product loses its identity and becomes simply “flounder”, so it will be difficult for the consumer to identify the species in the marketplace. There is also a premium live fish fishery, which mostly caters to the Asian market.

Import/export Statistics US Customs does not record trade of southern flounder individually, so there is no information regarding import or export activity of these two species.

Analysis of Criteria

Criterion 1: Inherent Vulnerability to Fishing Pressure Southern flounder is relatively short-lived and fast growing, with females growing significantly faster and reaching a larger size than males (FMRI 2003). Consequently, the fishery targets mostly females. Females are 50% mature at a length of 345 mm (13.6 inches) and approximately 1-2 years (Monaghan and Armstrong 2000). All females are thought to be mature after age 3; maximum length is 711 mm (28 inches) and maximum age is estimated to be at least 10 years (NCDMF unpublished data).

The life cycle of southern flounder is exemplified by figure 2. Once mature, southern flounder move offshore and are thought to spawn daily at approximately 30-66 meters depth (Benson 1982) from December through January (Fischer 1999 in GSMFC 2000). Tagged males have been shown to remain offshore once spawning has occurred. Females have been reported to spawn an average of 40,000 eggs each per spawn (Arnold 1977 in Reagan and Wingo 1985). More recent experiments with captive southern flounder suggest the number of eggs released

5 Seafood Watch® Southern Flounder Report April 6, 2004 varies from 1,000 to 28,900 per individual (GSMFC 2000). During the season, spawning frequency ranges from about 4-7 days (Fischer 1999 in GSMFC 2000). Larvae are pelagic for approximately two weeks; juveniles and adults migrate towards estuarine environments and reside there through the spring and summer months (Reagan and Wingo 1985; GSMFC 2000). Juveniles feed primarily on crustaceans until they reach adulthood, switching to a diet mainly of fish (NCDMF 2004).

Figure 2. Model of life stages for southern flounder (GSMFC 2000).

Synthesis Southern flounder is a fast growing, fecund, short-lived species (<10 years) that matures in less than 5 years. Seasonal migrations offshore make them more susceptible to fishing pressure during those times of the year. Overall though, this species is resilient to fishing pressure.

Inherent Vulnerability Rank: Vulnerable Neutral Resilient

Criterion 2: Status of Wild Stocks Generally speaking, there are two stocks of southern flounder in the southeast region, one in the GOM, and one in the Atlantic, mainly off North Carolina. These stocks, however, have been shown to be genetically similar and do not suggest independent stocks between GOM and the Atlantic coast (Blandon et al. 2001).

Atlantic Coast Stock Southern flounder is abundant in coastal waterways off North Carolina throughout spring and summer months, where it is targeted by commercial and recreational fishers. This is currently the most valuable finfish fishery in North Carolina, surpassing the historically important summer flounder in both catch and value (NCDMF 2004). Average commercial landings from 1993- 2002 were 3.8 million pounds (~ 1,700 mt; Fig. 3), while average recreational landings for the same time period were 150,600 lbs (NCDMF 2003b). In 2002, 3.5 million pounds (mp) of southern flounder were landed commercially, the 4th highest volume of finfish landed (NCDMF 2003a). The increase in fishing in the 1990s was caused by a decrease in summer flounder catch

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(causing a demand for other flounders) and an emerging and extremely lucrative live/sushi and sashimi market. During this time there were no species-specific regulations limiting fishing pressure, so effort (and catch) was essentially driven by the market.

Figure 3. Commercial landings and ex-vessel value of southern flounder in North Carolina during 1972-2002 (NCDMF 2004).

Figure 4. Commercial landings of southern flounder in North Carolina by pound nets, gill nets, and all other gears combined during 1972-2002 (NCDMF 2004).

The main methods used to catch southern flounder in North Carolina are gill nets and pound nets (Fig. 4). Traditionally pound nets were the primary gear used, but effort shifted with the early 1990s establishment of a deepwater gillnet fishery in Pamlico Sound. Currently, there are two different gillnet fisheries operating in the sound: deep-water (10-20 ft) and shallow-water (< 3 ft). The deep-water fishery consists of larger (25-45 ft) vessels fishing in the main basin of the

7 Seafood Watch® Southern Flounder Report April 6, 2004 sound from September through December (except for restricted areas, see Bycatch Criterion), while the shallow-water fishery consists of more traditional, smaller (15-25 ft) vessels operating along the Outer Banks from April through December (NCDMF 2004).

The North Carolina Department of Marine Fisheries (NCDMF) is the management body responsible for regulating the southern flounder stock in NC state waters. Managers were concerned for the stock upon observing an increase in fishing pressure and a decrease in recruitment in the 1990s. Based on the first assessment of southern flounder in North Carolina waters in 2001, the stock was considered overfished. However, due to insufficient or inconsistent data, the assessment was further modified and updated to include additional datasets compiled from the recreational gig and Recreational Commercial Gear License (RCGL) program in 2002 (NCDMF 2004).

The most recent stock assessment (Grist 2004) employed both fishery dependent (commercial and recreational landings, monitoring) and independent (juvenile and adult abundance surveys) into a Virtual Population Analysis (VPA) model. The assessor also evaluated catch-at-age (CAA), abundance indices, and population parameters. Results indicated spawning stock biomass (females only) decreased between 1993 and 1999, and increased to a high of 3.7 mp in 2002 (Fig. 5). Recruitment, measured as abundance of Young-of Year (age 0, YOY), has been highly variable over the study years (1991-2002), with a low of 2.8 mp in 1998 and a high of 10.8 mp in 2002 (Fig. 6). A surplus production model3 indicates that the biomass production in the stock averaged 3.8 mp from 1991-2002, while the average catch was 3.5 mp (Fig. 7). Also, for five out of the 12 years, catches exceeded production. Production is shown to have increased over catch in the last three years. However, the last few years in the model (‘terminal years’ 2000-2003) are highly uncertain due to the short data set (12 years) and the assumptions associated with the model. So, although there is a recent (last 3 years) upswing in the indices mentioned, this trend should be interpreted cautiously4.

3 Surplus production models are used to find the highest fishing mortality rate that can be offset by increased population growth, normally measured as a change in population biomass over time. The model uses data that has been aggregated across age classes. (From: Jennings et al. 2001. Marine Fisheries Ecology. Blackwell Science Ltd, p. 128). 4 Joe Grist. 2004. Personal Communication. NCDMF, PO Box 769, Moorehead City, NC 28557-0769.

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Figure 5. Spawning Stock biomass (females only) for southern flounder (NCDMF 2004). NOTE: Terminal year estimate (2002) is highly uncertain and should be interpreted cautiously.

Figure 6. Recruitment, measured as abundance at age-0 for southern flounder, based on VPA (NCDMF 2004). NOTE: Terminal year estimate (2003) is highly uncertain and should be interpreted cautiously.

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Figure 7. Mean surplus production and catch biomass for southern flounder based on VPA (NCDMF 2004).

Other findings included that 96% of the catch over the study years (1991-2002) consisted of females aged 0-2 years. Southern flounder females do not reach 100% maturity until age three, so a large proportion of the catch is removed before reproduction. Also, the average fishing mortality rate from 1991-2002 (F = 1.90) is thought to have depressed spawning stock biomass to approximately 5.4% of the unfished level; this is well below the percentage considered necessary to sustain most stocks (~20% SPR). The assessment model indicates that, based on back-calculated estimates of fishing mortality (1991-2002 average F = 1.90), overfishing has likely occurred every year since 1991. Based on these analyses, Grist (2004) concluded the stock is overfished, with overfishing occurring.

Gulf of Mexico Within the GOM, southern flounder stocks are assessed within the following regions: eastern Gulf (Florida), northern central Gulf (Louisiana), and western Gulf (Texas). Stock assessments were prepared by state agencies and were included in the GSMFC flounder FMP (GSMFC 2000). Stock assessments for the area indicate that the sex ratio of southern flounder is skewed; the degree to which this is natural is unknown. Music and Pafford (1984 in GSMFC 2000) reported a female to male ratio of 9.5:1 from a total of 116 fish, and other studies off Texas and Louisiana have shown a female to male ratio of about 6:1. It is probable that the lower male ratio is due to bycatch and may lead to decreased spawning success. Another reason for the skewed ratio would be sampling bias, as males tend to stay offshore and so would be underrepresented in a nearshore survey.

EASTERN GULF Southern flounder is available to commercial and recreational fishers off the both Florida coasts (Gulf and Atlantic side, Fig. 8; GSMFC 2000). Landings are split between sectors. In 2001 total flounder landings were 825,662 lbs, with approximately 70% from the recreational sector (FMRI 2003). On the Atlantic coast, recreational and commercial landings are thought to be composed of almost entirely southern flounder (FMRI 2003). Landings are highest during fall months, with the most prominent fishing methods being shrimp trawls, hook and line, or gig (GSMFC 2000).

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It is important to note that these landings do not specify what proportion of southern flounder comprise the total catch, or which gear type is used.

Figure 8. Total annual landings of flounders on the Atlantic and gulf coasts of Florida, 1982–2001 (FMRI 2003).

Landings have decreased since the 1980s; average landings from 1996-2000 were 22% lower than the historical average (1982-2001; FMRI 2003). Annual standardized catch per unit effort (CPUE) estimates for Atlantic recreational fishers were relatively stable until 1994, increased through 1997, and have shown a decline to 2001 (Fig. 9; FMRI 2003).

Figure 9. Annual standardized recreational total-catch rates (numbers) for southern flounder on the Atlantic coast of Florida (FMRI 2003).

Researchers at the Florida Marine Research Institute (FMRI) analyzed available biological, habitat, bycatch, and harvest data and were able to provide an overall description of the stock and fishery. They were unable, however, to adequately assess the status of southern or gulf founder stocks because the following information was unavailable:

• Species-specific landings data from commercial and recreational fisheries, • Age and size composition of commercial and recreational catch • Population dynamics such as fecundity, spawning seasonality, growth, and mortality, • Recruitment levels

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Therefore, the status of southern flounder along the eastern Gulf (i.e. west coast of Florida) is unknown at this time.

NORTHERN CENTRAL GULF This area is mainly focused on southern flounder stocks off Louisiana, where annual commercial and recreational harvests have averaged about 2 mp in the early 1990s, dropping off after 1995, particularly in the commercial sector (Fig. 10). Regulations implemented in 1995-1996 (e.g. prohibition of gillnets, restricted season, restricted permit qualifications) were largely responsible for the significant drop in landings (GSMFC 2000). Between 1997 and 1999 commercial shrimp trawlers were limited to no more than 100 lbs of flounder bycatch per trip; in 1999 this limit was repealed (LDWF 2004).

HARVEST OF SOUTHERN FLOUNDER IN LOUISIANA

3,500 3,000 2,500

2,000 1,500

Thousands 1,000 HARVEST (LBS) 500 0 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 YEAR RECREATIONAL COMMERCIAL

Figure 10. Total harvest of southern flounder in Louisiana waters, 1981-2002 (LDWF 2004).

The southern flounder stock off the coast of Louisiana is assessed annually by researchers at the Louisiana Department of Wildlife and Fisheries. The assessors use yield-per-recruit (YPR), spawning potential ratio (SPR), and catch curve analyses (disappearance rates) to estimate the impact of fishing pressure on the stock. Researchers estimated a standardized CPUE from various fishery-independent surveys and found a flat, slightly variable trend between 1981-2002 (Fig. 11). Marine recreational statistics survey CPUE was variable, with a slightly downward trend since 1990 (Fig. 12).

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2.0

1.5

1.0 Index

0.5

0.0 85/86 87/88 89/90 91/92 93/94 95/96 97/98 99/00 01/02 86/87 88/89 90/91 92/93 94/95 96/97 98/99 00/01 02/03 Year January - March October - December

Figure 11. Standardized CPUE of southern flounder in trammel nets, from Louisiana Marine Fisheries Division Monitoring Program (LDWF 2004).

2.50 2.25 2.00 1.75 1.50 1.25 1.00

Harvest/Trip 0.75 0.50 0.25 0.00 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 Year

Figure 12. CPUE of southern flounder in Louisiana NMFS Marine Recreational Fishery Statistics Survey (LDWF 2004).

Age and growth parameters from commercially sampled fish, estimates of sexual maturity and spawning potential (mean weight at age was used in place of fecundity estimates were unavailable) were incorporated into the YPR and SPR models to yield the following results:

“The results of YPR analysis indicate that if M=0.5 (the most conservative value within the range of estimates), the fishery in the years assessed (1997 - 2002) was operating between F0.1 and FMAX, with yields of 93% to 95% of maximum and SPR at 27% to 29%. An M of 0.8 (the highest value within the range examined) would produce yields of 57% to 60% of maximum with SPR at 50% to 54%.” (p. 1, LDWF 2004).

In the absence of a known biological reference point (threshold) for southern flounder, the Louisiana Legislature has determined an SPR value of 30% as appropriate conservation target (GSMFC 2000). If the SPR for the stock falls below this value, then remedial action must be taken. Although estimates are relatively uncertain and range from 27 % to 54% of SPR, it appears that the southern flounder stock in this area is near the conservation target. Researchers

13 Seafood Watch® Southern Flounder Report April 6, 2004 also note that more time is needed before the impact of recent regulations are observed in the stock assessment (LDWF 2004).

WESTERN GULF According to Stokes (1977 in GSMFC 2000), southern flounder is harvested in both the commercial and recreational sectors in Texas. Southern flounder dominates the overall flounder catch, and most are females (due to the 14” size restriction). Fishers targeted flounder with gillnets until they were banned in 1988 (GSMFC 2000). Since then, the main directed harvest method is use of gigs, and landings are highest from October through December (GSMFC 2000). Commercial landings have fluctuated over the last few decades, peaking last in 1987 at over 500,000lbs (Fig. 13). In 1997, bycatch (in shrimp trawls) accounted for 84% of the total female harvest and almost 100% of the male harvest. Recreationally, southern flounder ranks 9th in percent composition of the 81 total species caught by recreational anglers. Recreational catch has been relatively stable over time, averaging about 150,000lbs annually.

Figure 13. Commercial and recreational landings of female southern flounder, 1984-1997 (unpublished data in GSMFC 2000).

Texas Parks and Wildlife, Coastal Resources Division assessed southern flounder inhabiting the waters off Texas. Researchers used Sequential Population Analysis (SPA)5 to assess the impact of fishing pressure on stocks from 1984-1997. Commercial and recreational harvest data, fisheries independent data (state-sponsored catch surveys), and age and growth data were incorporated into the model. In addition to directed fishing mortality, mortality from shrimp trawl bycatch was also included, making the total estimate of fishing mortality more accurate. Results from the SPA show that age 1+ female flounders have been decreasing, and the population as of 1999 was about half its size in 1984 (GSMFC 2000). Based on the fishery- independent surveys, adult abundance (as measured by the catch of age 1+ flounder) has been declining over the study years. Abundance increased during 1996-97; the researcher suggested this was probably due to stricter regulations and a large 1996 year class (GSMFC 2000). In addition, the age and sex composition of the southern flounder stock has notably changed over

5 SPA is similar to virtual population analysis (VPA), using catch-at-age data to provide estimates of stock sizes and fishing mortality rates by age and year.

14 Seafood Watch® Southern Flounder Report April 6, 2004 time. Out of ~ 900 individuals that could be sexed, 17% were male, indicating a female: male ratio of 6:1. No males older than age 1 were sampled from Matagorda Bay, which also supports one of the largest shrimp fisheries in Texas. Biological reference points (Fmax,F 0.1) from the stock assessment indicate that female southern flounder are heavily exploited in this region, but that they “are probably not overfished” (GSMFC 2000).

Several studies between 1978 and the early 1990s have shown a significant amount of juvenile flounder bycatch in shrimp trawls (GSMFC 2000). This evidence suggests that large portions of flounders, mostly males (they are smaller than females and hence not targeted directly), are being removed as bycatch in shrimp trawls. Their removal may be limiting reproduction of the stock (GSMFC 2000). Based on this assessment, the southern flounder stock in the western Gulf appears to be in poor condition.

Synthesis The stock off North Carolina has recently received a thorough stock assessment, which concluded that the stock is overfished and experiencing overfishing. This situation is perceived as critical. For each of the three regions in the GOM (Eastern, North-central, Western), southern flounder stock assessments were hampered by poor fisheries data and uncertain conclusions were made. For this reason, southern flounder from the GOM should be considered with caution.

Status of the Stocks Rank: Critical (Atlantic - NC) Poor Data deficient (Gulf) Healthy

Criterion 3: Nature of Bycatch NOTE: Seafood Watch defines bycatch as catch that is landed but subsequently discarded (injured or dead) because it is of size, sex or composition. Bycatch does not include incidental catch (non-targeted catch) if it is utilized and is accounted for and managed in an appropriate way.

Atlantic Fishery In North Carolina the major gears used to catch southern flounder are gillnets and poundnets. A pound net is a heavy mesh net that is set up in shallow estuarine waters and acts as a trap for live fish (Fig. 14). It is very labor intensive to erect, so fishers usually leave the net through the season and return regularly to collect the catch. Due to the nature of the gear, fish (and other creatures) are trapped alive within the submerged pen. There may be some bycatch of other finfishes or protected species of sea turtle, but there appears to be very little mortality as fishers are able to release unwanted catch6. In addition, some nets have panels that allow for escapement of undersized fish (J. Grist. Pers. comm.).

6 John Burke. 2004. Personal Communication. NOAA Laboratory, 101 Pivers Island Road, Beaufort NC 28516.

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Figure 14. A schematic representation of a pound net (after Rounsefell 1975 in West et al. 1994)

The southern flounder gillnet fishery operating in Pamlico Sound has been shown to interact, often adversely, with three species of protected and endangered sea turtles: the Kemp's ridley (Lepidochelys kempii), loggerhead (Caretta caretta) and green (Chelonia mydas) turtles. Concerns over an increase in sea turtle strandings led NCDMF and NMFS to conduct observer trips in the fall of 2000 (Gearhart 2001). The findings were as follows:

”Monitoring of the deep-water fishery during the 2000 fishing season consisted of 13.1% observer coverage within the PSGNRA with 35 trips observed. Fourteen sea turtle interactions were observed involving four Kemp's ridleys, two greens, and eight loggerheads. Eight of these turtles were released alive; six were dead. [For the shallow gillnet fishery,] monitoring during the 2000 fishing season consisted of 4.3% observer coverage of the shallow-water, large-mesh fishery within the PSGNRA with 37 trips observed. Four sea turtle interactions were observed. All were green turtles. Three were released alive; one was dead.” (NOAA 2001).

Due to implemented closures and observer coverage, interactions with sea turtles have decreased. According to NCDMF Director Preston Pate, “Last year, only one turtle was found dead in a fishing net in the Pamlico Sound Gill Net Restricted Area [PSGRA] during the fall flounder season, compared to seven turtles in 2000" (NCDMF 2002). This reduction in catch indicates that managers and fishers are succeeding in reducing interactions with protected/endangered sea turtles. See Management Section (Criteria 5) for further explanation of regulations.

GOM: DIRECTED FISHERY Although fishing gear varies by state, the majority of targeted southern flounder are caught recreationally using small net, gig, and rod and reel. Commercial fishers targeting flounders may use a pound net, gig, seine (haul or trammel net), or handline. Gigging occurs mainly at night and involves wading into shallow waters, illuminating a flounder with bright light, and spearing it. Spears may be as simple as a sawed-off broom handle with a nail on the end. In some states

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(TX, MS) up to 25% of the commercial catch is from gigging (GSMFC 2000). In the Gulf, a vast majority of southern flounder is taken indirectly through commercial shrimp harvesting.

GOM: INCIDENTAL CATCH – SHRIMP TRAWL In Gulf states with significant shrimp trawl fleets, flounders are caught incidentally (i.e. as bycatch). Depending on state regulations, some or all of this catch – if it is of marketable size - is retained. Although retention of marketable bycatch species is preferable over their wasteful discard, the overall incidental take in commercial shrimp trawls has been widely criticized as excessive and detrimental to populations of other marine fauna (particularly sea turtles and red snapper, Lutjanus campechanus)7. Therefore, flounders (or other species) retained in bycatch operations must be evaluated separately from those in directed fisheries, where bycatch is minimal.

The exact ratio of non-shrimp bycatch in Gulf and Atlantic shrimp trawl fisheries remains difficult to quantify. NMFS data suggests a ratio of 10:1 existed in the 1970s, before measures were put in place to reduce growth overfishing of shrimp (Leard 1999). Estimates of the bycatch ratio for Florida shrimp trawls range from 6:1 to 1:1 (Jones8). Studies by the Texas Department of Parks and Wildlife found ratios in Texas state waters of approximately 4:1 (TPW 1999). Industry representative Sal Versaggi9 (2003) asserts that the Gulf and South Atlantic fishery has reduced the bycatch ratio from 10:1 to 3:1 since the mid-1980s. The best recent, non-industry estimates suggest that, for every pound of shrimp caught, about 4.5 pounds of bycatch are discarded in the U.S. South Atlantic and about 5.25 pounds of bycatch are discarded in the Gulf (Clucas 1997; NMFS 1998).

Synthesis Fishing gears used to target flounders directly involve little or no bycatch. However, shrimp trawls that take flounders incidentally have a significantly high bycatch rate for finfish, invertebrates, and endangered/protected sea turtles, making this type of fishing gear a high conservation concern.

Nature of Bycatch Rank: High (shrimp trawl) Medium (Gillnets, Pamlico Sound) Low (Pound nets/Gigs)

7 The list of references is large. See Cook (2003) The Magnitude and Impact of By-catch Mortality by Fishing Gear. FAO. Responsible Fisheries in the Marine Ecosystem. M. Sinclair & G. Valdimarsson eds. 8 Jones, Bob. 2003. Personal communication with Alice Cascorbi, by email, 12/15/03. Email [email protected] 9 Versaggi, Sal. 2003. Versaggi Shrimp company. Personal communication with Alice Cascorbi, by email, 12/18/03. Email [email protected]

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Criterion 4: Effect of Fishing Practices on Habitats and Ecosystems

DIRECTED FISHERIES – GOM/ATLANTIC (NC) Fishing gear used to target flounders commercially in the GOM consists mainly of smaller entangling nets (< 500ft2 for most states in which use of nets is still allowed) and spears (gig), which, compared with more invasive trawling gears, shows minimal signs of impacting habitat. Recreational fishers use rod and reel or spear, and fish either from shore or in small boats (GSMFC 2000). In a review of the fishing gear used in the Southeast Region of the US, Barnette (2001) concluded that except for use in areas of coral cover, the use of entangling nets on bottom habitat is minor. There is no evidence available concerning habitat impacts from gigging. However, based on the gear description from the GSMFC FMP for southern flounder (use of small boats at night to spear observed flounder) it would not appear that this type of gear affects bottom habitat. There may be some minor scarring and temporary turbidity if the motor were to come into contact with the bottom in very shallow areas, but this is likely avoided by fishers whenever possible. Off North Carolina, gillnets and pound nets are primarily used to catch southern flounder. Due to the static nature of the gear, this gear is thought to have minimal disturbance on habitat (West et al. 1994).

INCIDENTAL FISHERY – SHRIMP TRAWL About 91% of Gulf & South Atlantic shrimp is taken by otter trawls, in which large and heavy wooden “otter boards” drag along the bottom to spread the net. In the Gulf, many otter trawls are double or even quadruple-rigged (one vessel pulls two or four relatively small nets, instead of one large net). In a study evaluating fishing gear effects on bottom habitat in the GOM, Barnette (2001) concluded that, “given the available scientific information, it would appear that trawling has a minor physical impact to essential fish habitat in many areas of the Gulf of Mexico and South Atlantic. Trawls harvesting shrimp operate over sandy or muddy habitat areas. The major result of these activities would be sediment resuspension, which is a relatively minor and short- term impact” (p.42). He reiterates, however, that most of the areas that can be trawled have been trawled repeatedly for decades, and so “the empirical study of fishing effects is hampered by a lack of unfished control sites” (p. 42). Barnette (2001) concluded, “while it may be concluded that trawls have a minor overall physical effect when employed on sandy or muddy substrates, the available information does not provide sufficient detail to determine the overall or long-term effect of trawling on regional ecosystems” (p. 18).

Whether removal of southern flounder biomass has an effect on the ecosystem in general is questionable. Studies focusing on ecosystem impacts of fishing in the Gulf have yet to be conducted.

Synthesis The directed fishery for southern flounder in the GOM and off North Carolina is largely benign with respect to habitat and ecosystem effects. This is because the nature of the gear types (mainly pound nets and gigs) do not contact the seafloor in a mobile fashion. With respect to incidentally caught and retained flounders in the shrimp trawl fishery, Barnette’s review suggests that the soft-substrate habitats of interest for this report have not seen appreciable degradation due to trawling, but notes that a lack of control sites means that the available science cannot answer the question of whether long-term or permanent change has resulted from bottom trawling. Therefore, “science is uncertain”.

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Effect of Fishing Practices Rank: Severe Average/Uncertain (shrimp trawl) Benign (Directed fishery)

Criterion 5: Effectiveness of the Management Regime Because southern flounder mainly resides within state waters, management of flounder stocks and their respective fisheries rests with individual states. Certain federal mandates, such as SFA and MSFCMA are incorporated into state management plans, but the sustainability of stocks ultimately resides with individual states.

Atlantic stock management Because North Carolina has the largest southern flounder fishery in the Atlantic, evaluation is focused on this state. The passing of the Fisheries Reform Act in 1997 by the North Carolina General Assembly mandated that state fishery management plans (FMPs) must be developed by NCDMF for all commercially and recreationally important species. Managers have recently carried out a stock assessment and are planning to implement a southern flounder FMP in the fall of 2004 (Joe Grist, pers. comm.). Enforcement is carried out through observer programs, mandatory logbook reporting (since 1994), and dockside monitoring.

Southern flounder has historically been managed under the general ‘flounder’ harvest category (Grist 2004). There are no bag limits or quotas in place at this time, nor have there been limits on take in the past. Size-limit restrictions were implemented in 1988 for inshore flounder stocks at 13 inches (330 mm), for all species. The length at 50% maturity for southern flounder is 13.6 inches (345 mm; Monaghan and Armstrong 2000), so a large proportion (data suggests ~ 60% of catch is age 1) of immature fish are removed under this regulation. In October 2002 the size limit was increased to 14 inches, except within an area of the western Pamlico River where recreational fishers catch fish of a smaller average size (J. Grist, Pers. comm.). Based on the fact that over 90% of the catch is not fully mature, the size limit appears to be inadequate for this species and is likely a factor leading to its overfished status.

As the gillnet fishery expanded and concerns were raised regarding sea turtle interactions, NCDMF and NMFS gathered observer data to assess the situation. On December 10, 1999 NMFS issued an emergency rule closing a part of the sound to the use of gillnets larger than 5 inches (64 FR 70196). These nets were suspected to be a significant cause for turtle strandings (Gearhart 2001). In September 2001, NMFS again closed the waters of Pamlico Sound to fishing with gillnets of a mesh size larger than 41/4 inches, (NOAA 2001). In order to reopen a portion of the large-mesh fishery, NCDMF has applied (and received) an Incidental Take Permit (ITP) for each fishing year. The permit authorizes a certain amount of sea turtle takes in the southeastern area of the Pamlico Sound (PSGRA). In return, NCDMF is required to monitor the fishery closely and reduce sea turtle mortality by at least 50% from 1999 levels (NOAA 2001). The fishery will be closed prior to the end of the season if more than the allowable number of turtles are taken. This happened in the fall of 2000, when a high of 838 strandings occurred10 and the fishery was closed in October (NOAA 2001). However, in 2001, strandings decreased by 67% from 2000, demonstrating that the closure of the deep-water large-mesh fishery was effective in reducing bycatch and strandings of sea turtles (NOAA 2001).

10 NOTE: not all strandings are linked to the gillnet fishery.

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GOM Management Although employees of the Gulf states manage and assess stocks individually, they are also members of the Gulf States Marine Fisheries Commission (GSMFC). The GSMFC aids in marine resource management through development of FMPs, interjurisdictional fisheries management, research, and discussion of various issues affecting marine fisheries in the GOM. The states and the Commission have produced stock assessments for southern flounder, but because fisheries data were limited, conclusions are not robust. In the 2000 FMP, individual states expressed future management and research considerations that they hope will be addressed in future stock assessments.

Table 1: Individual State Regulations for the GOM regarding take of southern flounder (GSMFC 2000; FFWCC 2003; state fisheries websites). State & Agency Entry/Permit Gear Type Size/bag limit Quota Closed (Recreational) (Commercial) season, area Florida No limit, Seine, cast 12”TL; 10 No quota, 50 No (except (Fish & Wildlife Conservation $5,000/year nets fish/day lbs bycatch national Commission) permit required (<500ft2) (shrimp trawls) parks, etc.) http://floridaconservation.org/marine/ H&L, gig, allowed spear Alabama Limited to Entangling No size limit, No quota 1/1-10/1 (Dept. of Cons. & Natural Resources) fishers w/ >50% nets allowed No bag limit, nets http://www.dcnr.state.al.us/mr/regulations.htm income from w/ prohibited seafood restrictions; w/in no purse .50km of seines shoreline Louisiana (Dept. of Wildlife & LE for h&l, no Pole, line, No size limit, 10 No quota; Designated Fisheries) LE for other gig, various fish/day comm. bag is refuges http://www.wlf.state.la.us/apps/netgear/ gear cast net; also 10/day or and state index.asp?cn=lawlf&pid=18 entangling bycatch from wildlife nets shrimp trawl areas. prohibited. Texas (Parks & Wildlife Dept., Coastal Entry limited to No 14”TL; 10/day, No quota; 60 No. Resources) full-time fishers nets/traps 20 possession per day; http://www.tpwd.state.tx.us/publications allowed; incidental /annual/fish/index.phtml H&L, shrimp trawl trotline, sail take limited to line, gig <50% shrimp weight. Other incidental: 10/day. Mississippi (Dept. of Marine Limited to Entangling 12”TL; 15/day Quota 74,000 No. Resources) residents nets lb. October 1 http://www.dmr.state.ms.us/ degradable until Quota is only w/ Reached* restrictions; no purse seines, no traps allowed; H&L, trotline, gig H&L = hook & line, TL = total length (tip of snout to tip of tail) * Mike Brainard. Personal Communication. Mississippi Dept. Marine Resources.

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Synthesis State managers in the GOM have regulated fisheries through many means (see Table 1 above) to control fishing effort, preserve habitat, and sustain stocks. They have regulated fisheries to reduce bycatch and habitat impacts, and have traditional avenues for monitoring and enforcement of fishing regulations (US Coastguard, dockside monitoring, etc.). Management currently does not have enough information to conclude the status of southern flounder stocks in the GOM, and is therefore deemed only moderately effective. For the Atlantic stock, managers are now assessing the stock and implementing an FMP after the species has become overfished, making their effectiveness only moderate as well.

Effectiveness of Management Rank: Critical Ineffective Moderately effective Highly effective

Overall Evaluation and Seafood Ranking Southern flounder support US commercial and recreational fisheries along the coasts of the Gulf of Mexico (GOM) and Atlantic Ocean. This species is fast growing, short-lived (≤10 years) and matures quickly (< 5yrs). Stock status in three Gulf regions is uncertain due to the lack of species-specific fisheries dependent and/or robust independent data. In the inshore waters of North Carolina where the largest Atlantic fishery for this species occurs, southern flounder is considered overfished with overfishing occurring. This combination is perceived by Seafood Watch to be of critical concern to stock status. The directed commercial fishery for flounders uses pound nets, seines, hook and line, or gig, none of which have been shown to have significant bycatch or adversely affect habitat. Deep-water large mesh gillnets in Pamlico Sound, NC, have been shown to cause strandings of protected sea turtles, but measures have been taken to reduce the amount of interactions. Flounders incidentally caught and retained from shrimp trawl operations are of concern, as trawls have been shown to take a high proportion of other fishes, invertebrates, and sea turtles respective to shrimp catch. Trawls are thought to cause minor alterations to sea bottom habitat in the Gulf. Management is moderately effective at assessing southern flounder stocks, due to stock uncertainties caused by limited fisheries data (GOM) and failure to prevent overfishing (North Carolina).

Overall Seafood Rank

Avoid - Atlantic (North Carolina)

Good Alternative – Gulf of Mexico

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Acknowledgements

Seafood Watch staff would like to thank Steve Vanderkooy of the Gulf States Marine Fisheries Commission, Harry Blanchet of the Louisiana Department of Wildlife & Fisheries, and Joe Grist of the North Carolina Department of Marine Fisheries for their review of 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.

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