A Gulf Menhaden Deep Dive

Mario Campo
Fisheries Ecologist, Southeastern Louisiana University
Science and Policy Associate, American Saltwater Guides Association

This discussion explores the status of Gulf Menhaden stocks, their ecological and economic role in the northern Gulf of Mexico, and potential strategies for sustainable fishery management.

Forage Fish Overview 

The term “forage fish” addresses any fish that is predated (eaten) at some point of its life history, typically occurring greatest among juveniles. Over time, literature has coined forage fish as a label for abundant, schooling fish species that act as prey for an array of organisms such as predatory fishes, marine mammals, and sea birds (Nissar et al. 2023; Hilborn et al. 2017; Springer & Speckman, 1997). Common forage fish species occurring throughout many marine ecosystems include krill, sardine, anchovy, menhaden, and even squid (Chee et al. 2024, Hilborn et al. 2017). Forage fish are critical components of ecosystem foods webs as they transfer energy from the primary producers they eat (i.e., plankton), to higher trophic level predators that in turn, eat them (Chee et al. 2024, Berenshtein et al. 2023, Adams et al. 2018, Sagarese et al. 2016).

The important role forage fish provide to ecosystem food webs is well accepted, but the overall impact of forage fish abundance on predator species status is heavily debated (Free et al. 2021, Pikitch et al. 2018, Hilborn et al. 2017). Within the Atlantic and the Gulf, menhaden are highly regarded as critical forage fish to their respective marine ecosystems, and act as highly efficient energy transfer pathways to higher trophic level organisms (Robinson et al. 2015). From an economic, and fishery perspective, Gulf menhaden support the largest fishery in the Gulf, and the second largest in the USA, while providing high-level nutrition to predators including those favorably targeted by recreational fisheries (Sagarese et al. 2016, Vaughan et al. 2007). The menhaden’s historically robust economic and ecological value has contributed to their well-known description as “the most important fish in the sea” (Franklin et al. 2007). Given their ecological and economic significance, several respected studies have investigated the role of menhaden in predator diets and evaluated how harvest by the commercial reduction fishery possibly affects predator species through direct and indirect impacts (Chee et al. 2024, Berenshtein et al. 2024, Sagarese et al. 2016). Interestingly, the studies suggested that predator dependence upon menhaden occurred in the Atlantic for species like Striped Bass, but found dependence was not exhibited by any species in the Gulf, challenging the traditional idea that a global dependence is placed upon forage fish species by predators. This is likely due to the Gulf exhibiting greater biodiversity compared to the Atlantic which can possibly be attributed by several factors, and most easily explained by the Latitudinal Diversity Gradient (LDG) theory, where biodiversity has an inverse relationship with distance from the equator.

The Gulf’s rich biodiversity provides an abundant prey field for predatory species, which can be observed in results by Chee et al. 2024, and Sagarese et al. 2016, which strongly suggest predators are not forced to depend their forage requirements on a single prey species, i.e., Gulf menhaden. These findings further suggest that Gulf Menhaden compose on average only 2-3% of total diet composition of most predatory species in the northern Gulf. Key predators of Gulf menhaden were identified as juvenile King Mackerel, juvenile Spanish Mackerel, adult Spanish Mackerel, Red Drum, and Blacktip sharks, where juvenile King Mackerel have the greatest diet composition of Gulf Menhaden at 11.8% (Chee et al. 2024, Sagarese et al. 2016); (Figure 1).

            Interestingly, results from Chee et al. 2024, and Sagarese et al. 2016, suggested the total contribution of identified forage fish species to predator’s diets was approximately 11%, with a broad diversity of prey species supporting predators’ dietary requirements (Figure 2). 

The direct and indirect impacts of the commercial reduction fishery on predatory species abundances was modeled by Berenshtein et al. 2024, along with predator-prey interactions involving Gulf menhaden. Results from this study suggests that Gulf menhaden predatory species most sensitive to changes in menhaden fishing mortality (F) were King and Spanish mackerels, Tuna, Blacktip shark, Sea trout, and Red Drum. These results largely corroborate with findings from Chee et al. 2024, and Sagarese et al. 2016, when comparing predatory species diet composition, and sensitivity to changes in the commercial reduction fishery. When focusing solely on purse seine effort, and bycatch impact, the most negatively affected groups were a wide range of organisms including inshore coastal piscivores, Sea trout, demersal invertebrate feeders, oceanic piscivores, and coastal sharks. Such results, suggest a pattern that when modeled at its peak historic effort, commercial reduction harvest of menhaden contributed to a reduction in some capacity of predator biomass, whether through fishing mortality on menhaden, purse seine effort (bycatch), or by both. Berenshtein et al. 2024, applied the Ecopath with Ecosim (EwE) model, which was reported to have effectively identified an array of predator prey interactions, and quantified contribution of menhaden abundance to predator diets, noting that menhaden in year age classes 0–3 were the most frequently consumed. However, consistent with Chee et al. 2024 and Sagarese et al. 2016, the overall results suggested a diverse prey base present in the northern Gulf discourages any single predator species from being strongly dependent on menhaden. Rather, menhaden are observed to serve as a quality supporting food source, and predator diet composition likely varies seasonally.

Gulf Menhaden Stock Status 

Recent studies have not only helped reshape our understanding of the Gulf menhaden’s role in marine ecosystems through trophic dynamics, but findings from Brown-Peterson et al. 2017, suggest that the Gulf menhaden’s spawning season of 5.5 months is longer than previously understood, leading to a benchmark stock assessment in 2018 (Schueller, 2024; Jones, 2023). Since the benchmark assessment in 2018, there has been a 2021 stock assessment update, followed by a 2024 update based on a recommended three-year operational assessment timeline by the Menhaden Advisory Committee (MAC), with next stock update to occur in 2027 (Schueller, 2024). The most recent assessment (2024) incorporated data from years 1977-2023 updating data such as commercial reduction, commercial bait, and recreational landings; age compositions from the commercial reduction landings; the coastwide juvenile abundance index – based on seine surveys; the adult abundance index – based on a gillnet survey; and length compositions from the gillnet survey (Schueller, 2024). A maximum sustainable yield value (MSY) was unavailable for the assessed stock due to an unidentified stock-recruit relationship, and an absent peak from the yield curve (VanderKooy, 2024), therefore spawning stock biomass (SSB) based on fecundity, and fishing mortality (F) were measured against threshold benchmarks (reference points) of SSB_{25% at F=0}, and F=M to assess stock status (Schueller, 2024). In explanatory terms, reference point thresholds: SSB_{25%, F=0}, and F=M can be explained as, “if fishing mortality = 0, the population would still have 25% of its SSB”, if the SSB falls below this point, the stock would be determined as “overfished”, i.e., not enough adults to replenish the stock; while F=M refers to mortality where “if fishing mortality (F) exceeds natural mortality (M) overfishing occurs”, where fishing effort removes fish faster than nature can replace them. In essence, the term “overfished” pertains to biomass, while “overfishing” pertains to fishing pressure. 

            The 2024 Gulf menhaden stock assessment indicated that the stock is not experiencing overfishing, and is not overfished (Schueller, 2024). Results from the 2024 assessment align with results from the 2021 assessment, where stock trends including trajectory and magnitude remain highly similar, and an inverse relationship between fishing mortality (F), and SSB is observed (Figure 2). Notably, the seine index used, indicated years with the largest number of recruits were 2011, 2014, and 2018, while model predicted length compositions from the gillnet index, and model predicted age compositions from the commercial reduction fishery corroborated with observed data across majority of years in the timeframe assessed (1977-2023) (Schueller, 2024). Fishing mortality (F) was observed to be greatest between 1977-2000, with the peak fishing mortality in the 1990s. Since 2000, fishing mortality has decreased, and remained variable yet stable since around 2010 (Figure 3). Model estimates from the 2024 stock assessment suggest that fishing mortality between 2020-2023 were among the lowest values in the entire 46-year time series assessed, with results of stock status yielding a low degree of uncertainty (Schueller, 2024). Contrasting reduction fishery effort to Gulf menhaden biomass removed, commercial harvest recorded an average annual harvest greater than 800,000 metric tons in the 1977-2000 timeframe, while the average commercial harvest has stabilized in the 400,000 – 500,000 metric ton range over the last decade (Schueller, 2024). Moving forward, an array of research recommendations and priorities are to be addressed at both the single species, and ecosystem-based scales. As more data is collected, and advancements are made in the northern Gulf of Mexico (nGOM) Ecopath with Ecosim (EwE) model, an ecosystem-based approach, utilizing ecological reference points is a high priority goal to be implemented for the advancement of marine fisheries management in the Gulf.

Gulf Menhaden Bycatch Results 

To better understand the direct and indirect impacts of the Gulf menhaden commercial reduction fishery, a bycatch characterization study was conducted during the 2024 Gulf menhaden commercial purse seine fishing season (April 15^th – October 31^st) by LGL Ecological Research Associates, to assess the magnitude of fishing mortality for discarded species (Raborn et al. 2024). Approximately 94% of commercial landings have occurred in Louisiana state waters by vessels operating out of three processing plants: Empire, LA (Westbank Fisheries), Abbeville, LA (Omega Protein; Ocean Harvesters), and Moss Point, MS (Omega Protein; Ocean Harvesters) (Raborn et al. 2024). Despite previous bycatch studies occurring roughly every decade, prior studies were conducted strictly at processing plants, failing to document the number and fate of bycatch release during operations on the water (Raborn et al. 2024, De Silva et al. 2001, Pulver and Scott-Denton, 2012). At sea operation of the commercial fishery are anchored by primary fishing vessels designated for transport of gear, and catch between processing plants, and fishing grounds. Fishing vessels haul two, smaller purse boats that are used to target, and set purse seine nets on identified schools of menhaden, typically found by a spotter aircraft overhead. Purse seines utilized by the commercial fishery average 1,000 – 1,400 ft. long, and 65 – 90 ft. deep, with 1 ¾ mesh size and slight variation observed among vessels (Raborn et al. 2024). Additional vessels known as run boats or “tenders” are specifically utilized to transfer catch from the purse nets into their own holds for transport. Catch including menhaden, and incidental bycatch is transported from the purse seine into the run boat hold via the run boat’s 25-cm diameter suction hose, fixed with a hose cage, i.e., bycatch exclusion device (BED). The hose cage acts as a mechanism to reduce bycatch by excluding large individuals from entering the hose. Smaller individuals that bypass the hose cage are transported through the hose, and passed over an excluder grate, acting as a second bycatch exclusion device. Individuals too large to pass through the excluder grate are directed off of the vessel via a release shoot, smaller bycatch and menhaden that pass through the excluder grate are sorted through additional sorting shoots by the onboard crew (Raborn et al. 2024).

At the conclusion of the pumping process, large individuals remaining in the purse seine net are then rolled over the float line, and released. This indicates that there are two functions of bycatch released during a set, being (1) individuals excluded by the hose cage, and rolled over the float line by crew (rollover bycatch), and (2) individuals that pass through the suction hose, and do not fit through the excluder grate, then released via the release shoot (chute bycatch), all individuals that fit through the excluder grate and sorted by onboard crew are classified as retained bycatch (Raborn et al. 2024). Interestingly, hose cage dimensions among vessels were observed to have considerable variation such as hose cage diameter, hose opening diameter, number of hose cage rows, largest side trapezoid area, largest end trapezoid area, total cage length, presence/absence of cage fenders, house cage total area / volume, and excluder grate spacing. A principal component analysis (PCA) was employed to summarize the variation of hose cages among vessels using the identified variables, and suggested that differences in dimensions explained 68% of hose cage variation among vessels (Raborn et al. 2024). This is significant to consider, when acknowledging hose cages serve a critical role in the first line of defense of reducing incidental bycatch. 

            During the 2024 season, a total of 13,144 purse seine sets were fished in Louisiana state waters, or adjacent federal waters (Figure 4). Sets were documented across a depth gradient from 10-48ft, in salinities that ranged from brackish 3 ppt to marine 32ppt (Raborn et al. 2024). 

Commercial effort throughout the 2024 season averaged an estimated 85,700 standard menhaden per set, with 49 sets containing an estimated 540,000 standard menhaden or more (1 standard menhaden = 0.3kg) (Raborn et al. 2024).  Average net set depths were observed to be approximately 14.8ft, with a high frequency of sets located in Breton Sound (LA state waters) adjacent to the Chandeleur Island complex. The average depth of net sets, and proximity of sets to the Chandeleur Island complex are of concern due to possible impacts to reproductive dynamics of non-target species, such as those of recreational importance including Red Drum, and Spotted Seatrout. Nearshore barrier island complexes, such as the Chandeleur Island complex have been identified as critical habitat for high density spawning aggregations of non-target species such as Red Drum, with peak spawning aggregations occurring for months August-October, coinciding with the final months of the commercial menhaden fishing season (Red Drum Technical Task Force, 2023). Considering this temporal overlap, the commercial menhaden fishery could potentially contribute direct, and indirect impacts to the reproductive dynamics of non-target species. An example of a direct impact would be removal of non-target species spawning biomass, i.e., Red Drum, Spotted Seatrout, etc. from the ecosystem through bycatch during spawning months, assuming a high bycatch mortality rate. An example of a potential indirect impact occurs after the spawning of non-target species, when tidal movements transport larval fishes into estuarine habitats for early juvenile development. Concern arises from the overlap between average depth of purse seine nets and average depth range of larval fishes, suggesting commercial menhaden fishing operations may disrupt larval transport into natal estuaries, ultimately suppressing future recruitment (Red Drum Technical Task Force, 2023; Lyczkowski-Shultz et al. 1988). 

            Incidental bycatch was reported as 4.57%N (total number of individuals) during the 2024 commercial reduction fishery season, the percentage is relevant to the “all catch” value (all bycatch and menhaden catch – individuals) reported as a total of 3,187,720,402, which means the 4.57%N bycatch value is equivalent to 145,804,257 individuals comprising the total (roll-over, release chute, retained) incidental bycatch (Raborn et al. 2024). Notably, of the total bycatch value, 145,519,692 bycatch individuals were retained, while 145,095 were released via roll-over, and 139,470 were released via the onboard release chute.

            Over sixty species were identified as incidental bycatch during the 2024 including Red Drum, Spotted Seatrout, Southern Flounder, King Mackerel, Spanish Mackerel, and Atlantic Tarpon (Raborn et al. 2024). Post release survival estimates, and overall condition were reported based upon a season long onboard holding study conducted as part of bycatch study. Post release estimates were reported as 73-88% survival in rollover bycatch, while survival in the release chute of those same species was significantly lower at 2-39%, all retained bycatch was assumed as 0% survival (Raborn et al. 2024). Red Drum, and Black Drum were observed to yield 83.91%, and 87.82% survival in roll-over bycatch, while yielding a mere 2.0%, and 2.1% survival in chute bycatch, respectively. This relationship was also observed in Gaff-topsail catfish, where 73.46% survival was observed in rollover bycatch, while only 39.1% survival in chute bycatch. Condition estimates applied to total observed species in rollover, and chute bycatch scenarios suggest a strong relationship exists between survival, and bycatch scenario, with rollover bycatch yielding significantly greater condition and survival probability compared to chute bycatch (Raborn et al. 2024). 

            Variation of hose cage dimensions among commercial vessels resulted in events where bycatch up to 1.6m (63in) could enter the suction hose becoming chute or retained bycatch, drastically reducing survival probability (Raborn et al. 2024). Non-standardized hose cage dimensions proved costly for smaller bodied species such as the top three retained bycatch species: Atlantic Croaker, Sand Seatrout, and Spot, which contributed 80,592,690; 24,750,238; and 11,685,469 individuals to the retained bycatch respectively. Released bycatch (rollover + chute) reported a high frequency of Gaff-topsail catfish, Cownose Ray, Red Drum, and Black Drum. Total estimated released bycatch of Gaff-topsail catfish was 63,589 individuals: (13,809 rollover; 49,780 chute). Total estimated released bycatch of Red Drum was 44,593 individuals: (26,752 rollover; 17,841 chute). Total estimated released bycatch of Black Drum was 25,637 individuals: (18,680 rollover; 6,957 chute). Comparatively, total estimated retained bycatch of individuals for Gaff-topsail catfish, Red Drum, and Black Drum were: 2,985,451; 8,354; and 48,178 respectively (Raborn et al. 2024). 

            Considering Red Drum specifically, those in released bycatch (44,593 individuals) had an estimated mean length of 37.2 inches in the rollover, and 35.6 inches in the chute. Regarding the estimated means of Red Drum involved in bycatch, adult specimens reach sexual maturity around age 5, typically measuring 27+ inches for both male and females at that time (Winner et al. 2014). It is suggested that a large percentage of Red Drum involved in incidental bycatch are sexually mature, and members of the population’s spawning stock. This is supported by observations in the bycatch study where Red Drum females exhibited signs of fully developed oocytes (eggs) in the months of August, September, and October. Such observations further suggest purse seine operations by the commercial menhaden fishery pose potential impacts (direct and indirect) to the reproductive dynamics of non-target species, including those important to recreational fisheries. 

Management Approaches

Debates have long contrasted the impacts of commercial and recreational fisheries, with recreational user groups often attributing population declines either to government mismanagement or to overexploitation by commercial fisheries (Cook and Cowx, 2006; Walters and Martell, 2004). At the conversation’s foundation arises the simple need to balance utility tradeoffs of two broad user groups interested in a shared resource. Historically in fisheries, if a population or stock experiences some form of alteration over time, the “blame game” is a second nature response between industry and recreational groups, but truthfully both play a role in the trajectory of fish stocks (Cook and Cowx, 2006; Walters and Martell, 2004). For instance, a common idea by recreational fishermen is that recreational landings of a target species could not compare to the quantity of landings by the commercial sector. Relevant to the discussion, this can be exemplified through the comparison of recreational landings of Red Drum, compared to the quantity of Red Drum interacted with by the commercial menhaden fishery through incidental bycatch. As previously mentioned, for the 2024 commercial menhaden fishing season there was a total bycatch of 52,947 Red Drum including both released, and retained bycatch, while annual recreational landings of Red Drum for 2023 was just shy of 750,000 landings (DuBose et al. 2024; Raborn et al. 2024). It is important to consider that of the total Red Drum bycatch, the estimated 26,572 in the rollover had an approximate 83% survival upon release, while the 750,000 recreational landings are considered harvested fish with 0% survival. Understanding this creates accountability, providing a framework for cohesive management through cooperation of user groups understanding that the action of removing target, or non-target species from the water, regardless of sector; recreation or commercial, can impact the trajectory, and overall status of populations (Cook and Cowx, 2006). 

• Coastwide Buffer Zones

            The Louisiana Department of Wildlife and Fisheries (LDWF) established a coastwide buffer zone as a spatial boundary to reduce pressure of commercial Gulf menhaden operations in shallow water habitat, and reduce user group conflict with inshore recreational fishermen. The buffer zone is described as a one-half mile buffer along the coast, with an extended 1-mile buffer at Grand Terre, Elmers Island, and Holly Beach, and a three-mile buffer at Grand Isle. The buffer zone receives broad public support, predominantly from recreational fishermen, with continued arguments by stakeholders that the one-half mile coastwide buffer zone in place needs to be extended even further (Webre, 2024). Although the buffer zone is designed to reduce impacts on benthic habitat by limiting shallow-water operations, the estimated mean purse seine set depth of 14.5 ft, along with the high frequency of demersal species observed in incidental bycatch, suggests that purse seine efforts likely still affect benthic habitats by targeting deeper portions of the water column rather than the mid-water column as intended (Raborn et al. 2024). Additionally, the 2024 bycatch study used a Generalized Additive Mixed Effects Model (GAMM) to analyze the relationship between purse seine depth and incidental bycatch composition. Results indicated that depth does not reduce the overall quantity of bycatch, but instead shifts species composition due to species-specific habitat preferences along depth gradients (Raborn et al. 2024). Additionally, it should be understood that fish – like most occurring things in nature are not randomly distributed throughout the environment. A process described as the forage arena theory drives ecological interactions resulting in varying relative abundances of organisms, dependent on habitat, and forage conditions (Walters and Martell, 2004). Given the complexity, and variability present in natural systems, distribution of fish species is highly dependent on a multitude of factors, therefore it would be naïve, and misleading to suggest simply implementing a spatial constraint in the form of extending the coastwide buffer zone will resolve bycatch issues. Those lobbying strictly for an extension of the coastwide buffer zone would foster the creation of an “out of sight, out of mind” painted by a façade of feel-good conservation. Extending the coastwide buffer zone will contribute to balancing tradeoffs among user groups by minimizing spatial conflicts, rather than eliminating the occurrence of incidental bycatch. To further minimize spatial conflicts between commercial and recreational user groups, a vessel specific buffer should be established to limit the encroachment, and over-taking of fishing grounds by a user group while the other is actively fishing. 

1. Optimum Sustainable Exploitation Rate

            Regarding the Gulf Menhaden stock, the 2024 stock assessment (Schueller, 2024) reported that the stock is not overfished, nor experiencing overfishing. Recent studies suggest the diverse prey base of the norther Gulf supports predators foraging requirements, without the need to rely on a single species compared to their predatory constituents in the Atlantic (Berenshtein et al. 2024; Chee et al. 2024; Sagarese et al. 2016). Economically, Gulf Menhaden support the largest fishery in the Gulf, and the second largest fishery in the Unites States, providing an array of processed products, i.e., fish meal (commonly used for feed in fish hatcheries), and commercial fishing job opportunities. Implementation of an optimum sustainable exploitation rate would further contribute to the sustainability, and resiliency of not only the Gulf Menhaden stock, but also populations of the higher trophic species they support, while boosting economic value of harvested Gulf Menhaden. 

1. Temporal Restriction

            Results from Brown-Peterson et al. 2017 suggested that the Gulf Menhaden spawning season of 5.5 months is longer than previously understood. Within the study, it is reported that a high percentage of Gulf Menhaden spawn during mid-late October, during the conclusion of the commercial fishing season placing them at risk of harvest. A potential route to protect the abundance of spawning Gulf Menhaden susceptible to industry harvest would be implementing a temporal constraint by decreasing the commercial season from October 31, to an appropriate mid-October date. October was also one of the months identified where the greatest abundance of spawning Red Drum was caught as incidental bycatch (Raborn et al. 2024). Considering this, a temporal constraint on the commercial season would likely contribute positive effects beyond the Gulf Menhaden stock.

1. Standardization of Bycatch Excluder Devices

            As mentioned in the bycatch section, hose cages fitted on each vessel had nine-dimension variables that collectively attributed to nearly 70% of size variation among suction hose cages (Raborn et al. 2024). In some scenarios, individuals measuring up to 1.6m (63 inches) was able to enter the hose and drastically reduce survivability by becoming chute or retained bycatch. A straightforward way to address this issue is by standardizing dimensions of hose cages among vessels. Despite its simplistic reasoning, this should be considered high priority when acknowledging the differences of survivability between rollover bycatch, and the others. 

• Onboard Bycatch Monitoring

            Incorporating on-board cameras onto commercial fishery vessels would create a practical way to monitor incidental bycatch, and leverage artificial intelligence (AI) software to identify fish counts, species, and measurements. Utilizing camera systems on vessels would yield greater cost, and time efficiency compared to onboard personnel, while AI software would help create a robust network of historic, and near real-time incidental bycatch data. 

• Ecosystem Based Fisheries Management

            Ecosystem Based Fisheries Management (EBFM) should be continued made a priority, with the advancement of the northern Gulf EwE, and development of ecosystem-based reference points. Applying an ecosystem-based framework would provide the ability to assess, and manage Gulf fisheries in a holistic, cohesive manner taking into account both socioeconomic, and socioecological relationships along with trophic dynamics, resource competition, along with habitat and climatic impacts. Implementation of EBFM would provide a more detailed framework of guiding future management decisions, and weighing tradeoffs, promoting sustainable Gulf fisheries. 

• Louisiana Revised Statutes for Management

            Management of the Gulf Menhaden fishery in Louisiana state waters is made possible by LA RS 56:638.1 which states “ Recognizing that there are ever-increasing numbers of both sport and commercial fishermen utilizing the waters of the state for recreational and commercial pursuits resulting in conflicts over limited space and competition for the same fish, and acknowledging that both the sport and commercial fishing industries are vital to the economy of the coastal region and the entire state, the fishery standards for conservation, management, and sustainability of all species of fish are hereby declared to be fair and in the best interest of the state.”. Along with LA RS 36:601A which states “The control and supervision of the wildlife of the state, including all aquatic life, is vested in the Louisiana Wildlife and Fisheries Commission. The commission shall be in the executive branch and shall consist of seven members appointed by the governor, subject to confirmation by the Senate.” Above listed revised statutes supply LDWF, and the Louisiana Department of Wildlife and Fisheries Commission the authority to enact management of Gulf Menhaden within state waters, given management is in the best interest of the state.

Conclusion

Despite the traditional thought of Gulf Menhaden being a keystone species, recent studies suggest that they average 2-3% of predatory species’ diets, and there is no reliance placed upon their abundance by those species. It should be noted that the cited studies assessed diet composition of species across the northern Gulf, but site-specific feeding patterns likely occur among sub-populations depending on locality. A 2024 stock assessment update reported the Gulf Menhaden stock is not overfished, nor experiencing overfishing, while suggesting commercial fishing mortality is significantly less compared to historic values. A 2024 bycatch report suggested that of the three difference bycatch scenarios (1) rollover, (2) chute, and (3) retained; rollover bycatch experience a significantly higher survivability compared to the others, but the variation of hose cage dimensions among vessels contributed a large number of individuals becoming chute, and retained bycatch resulting, in severely decreased survivability. 

            A range of management approaches were identified, including spatial restrictions such as buffer zones, harvest restrictions through optimum sustainable exploitation rates, and temporal restrictions to protect spawning fish species such as Gulf Menhaden, and Red Drum. Included were measures to efficiently monitor bycatch, such as on-board cameras utilizing AI software, and for the continued development of EBFM. These management approaches can be used in conjunction with one another to form a cohesive approach that accounts for recreational and commercial fishery utilities and balance identified tradeoffs in the most efficient way possible. Ultimately, the Gulf Menhaden is not be a keystone species, or “the most important fish in the sea” as previously thought, but it serves a robust economic, and ecological role through its harvest in the commercial fishery, and broad support of predatory species in trophic dynamics. With the appropriate revised statutes in place, and a three-year stock assessment update timeframe, proactive management by the state is made possible to ensure the continued sustainability, and productivity of one of the Gulf’s most important players, the Gulf Menhaden. 

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