During their summer meeting in August, the Atlantic States Marine Fisheries Commission (ASMFC) approved Addendum VI to Amendment 6 to the Interstate Fishery Management Plan for Atlantic Striped Bass. This action was taken in response to the findings of the 2018 benchmark stock assessment for striped bass which found the stock to be overfished and overfishing occurring. Such designations trigger the Striped Bass board to take action to reduce fishing mortality below the fishing mortality threshold of 0.24. Based on the current estimates of fishing mortality, the ASMFC finds that total removals of striped bass needs to be reduced by 18% relative to 2017 removals. The ASMFC is expected to take action on Addendum VI at its annual meeting later this fall with state partners expected to have measures in place for the start of the 2020 fishing season.
The Atlantic Striped Bass stock was declared rebuilt in 1995 following an aggressive rebuilding plan that drastically reduced landings in order to protect a few strong year classes. The thought was that if extreme protection was afforded to these strong cohorts of fish, that in 5 to 6 years they would recruit into the fishery and bolster the spawning stock biomass. Since that rebuilding milestone achieved in 1995, the striped bass stock has continued to grow, peaking in 2003-2004, demonstrating strong recruitment and expanding its range. However, a decline in female spawning stock biomass was observed beginning in 2009 following several years of below average recruitment. The current estimate of spawning stock biomass is 151 million pounds which is below the threshold of 202 million pounds.
It is important to note that the current state of striped bass is far from dire and it is helpful to understand the historic context of this fishery. Looking at the figure above that is included in the 2018 benchmark assessment; it is apparent that the striped bass stock remains in far better condition that it was in the 1980’s when rebuilding was first initiated for the fishery. The decline in spawning stock biomass in the present is primarily the result of below average recruitment which can be seen in the period of 2005 through 2010. It is interesting to note that these low recruitment events occurred during a period of time when spawning stock biomass was in a state of historic high abundance. With striped bass, recruitment is largely driven by weather and environmental and water quality conditions, not fishing mortality. The chart illustrates the strong 2015 and 2016 year classes which will begin to enter the fishery in 2019 and 2020 and help elevate spawning stock biomass during those years. Other important items to note are that the in the entire history of striped bass management, the stock size has never exceed the spawning stock biomass target which is slightly over 250 million pounds. This fact makes one question if the rebuilding targets and other biological reference points for striped bass are appropriate. While the current status of striped bass does warrant some management adjustments, drastic measures are not needed at this time nor is a formal rebuilding plan needed for this stock. Modest adjustments to fishing mortality and efforts to minimize recreational discard mortality now may not result in sufficient improvements to spawning stock biomass in the near future if other management problems, primarily dead discards, are not addressed.
Addendum VI’s objective is to reduce total removals (harvest and discard mortality) of striped bass by 18%. The addendum includes two options to achieve this goal. One option would apply an 18% reduction equally among commercial and recreational sector while the other option would apply a 1.8% reduction to the commercial sector and a 20% reduction to the recreational sector. Under each option there are a suite of sub-options specific to the commercial and recreational fisheries and the Chesapeake Bay and coastal migratory fisheries. Those options maintain a 1 fish bag limit in the ocean fishery and increase the minimum size limit (32”) to a series of slot limit options (28”-34”, 32”-40” and 30”-to be determined). The Chesapeake Bay fishery has a series of options with variable bag limits and size (minimum size and slot) limits. States may also submit measures not included in Addendum VI but achieving the required 18% total removal reduction given that they are reviewed and approved by the ASMFC Technical Committee and Striped Bass Management Board. Addendum VI also includes options to mandate or encourage the use of circle hooks in order to reduce recreational release mortality which according to the 2018 assessment, accounts for 49% of total removals in 2018. Managers currently assume that 9% of all caught and released by recreational fishermen die. Many of the measures included in Addendum VI are expected to increase dead discards in the recreational sector.
Options in Addendum VI seem to focus on reducing landings but they are expected to increase dead discard mortality. This will surely be a point of contention as the Addendum progresses towards final approval.
Beginning this week, ASMFC will be holding public hearings on Addendum VI to gauge the interests of the commercial and recreational fishermen with regards to preferred options designed to achieve the 18% total removal reduction relative to 2017. Fishermen should keep in mind that the performance of the 2018 ocean striped bass fishery operating under the current regulations achieved a 18% reduction relative to 2017. Thus, status quo is viable option for this fishery. Addendum VI as well as the public hearing schedule can be viewed here.
The RFA believes it is important to address the following points as this process moves forward. As stated above, environmental factors play a critical role in the success and strength each year class. Striped bass return to freshwater water each spring to spawn and the Chesapeake Bay is the largest producer area which contributes the most to the coastal migratory stock. Water quality issues have been an ongoing issue in the Chesapeake and given the span and complexity of its water shed, it is extremely unlikely that significant water quality improvement will be made in the near future. The Chesapeake Bay is also far more variable of a spawning area due to weather’s greater influence on the Bay compared to other spawning areas such as Hudson River and some other northeast coastal tributaries that prove to have successful spawning occurring. For this reason, the long-term outlook for the Chesapeake Bay serving as a prime spawning area is bleak. RFA suggests that greater focus should be placed on spawning systems like the Hudson River, which currently is the second largest production area for Atlantic Striped Bass. The Hudson tends to show more stability in terms of year class strength, has had better water quality and seems to be less influenced by weather variability.
The ASMFC, in conjunction with state and federal partners, needs to make resources available to identify and monitor new emerging or reinvigorated spawning areas for striped bass. RFA also recommends a joint Canadian/American study to get a clearer picture on the changes in striped bass coastal distribution and whether their increase population is comprised of American coastal stocks. Greater emphasis on reducing fishing pressure and release mortality on pre-spawn striped bass heading into the Hudson River and other spawning river capillary should be considered. This type of protection would need to be a joint effort between states that have shared waters leading up to the spawning grounds on the Hudson and other productive tributaries.
States with commercial striped bass fisheries should consider implementing limited entry and participation criteria to prevent to the wanton distribution of commercial fishing permits. If the states’ commercial striped bass quota cannot be achieved without luring recreational fishermen to contribute to the commercial landings then a reallocation discussion should be initiated. Bag limits for captains and mates on for-hire vessels should be eliminated. Furthermore, circle hooks, as defined by the ASMFC 2009 technical document, should be mandatory when using bait for striped bass. The practice of snag and drop and yo-yoing with j-hooks or multi barb hooks (treble hooks) while fishing with baits needs to stop. With nearly 50% of the mortality on striped bass coming from released fish in the recreational sector, all efforts to reduce discard mortality should be pursued. Mandatory use of circle hooks in bait fishing would be a significant step to that goal.
The issue of release mortality cannot be taken lightly and it is critical to understand where it comes from. According to NOAA Fisheries, the total number of striped bass released alive by recreational fishermen amounted to 41,716,648 fish in 2017. Broke down by mode (see Figure 2.), 67% of those fish are attributed to anglers fishing on private boats, 29% to anglers fishing from shore or piers, and just 2% attributed to party and charter boats. Of the 41 million striped bass released by recreational anglers, 3.42 million of those fish are assumed to have died following release which exceeds the number harvested at 2.93 million pounds. Based on these numbers, its clear that any management option that aims to reduce total mortality on striped bass must address release mortality. It is the opinion of the RFA that any management option that simply moves mortality from harvest to discard mortality is a waste of a natural resource and unnecessarily excluded traditional uses of the striped bass fishery.
For assessment and management purposes, the ASMFC assumes that 9% of all striped bass that are released alive by recreational fishermen will die. The accepted release mortality value of 9% is based on a series of work done on the topic that looked at all aspects of the fishery including gear type, experience level, water conditions (salinity, temperature, dissolved oxygen, ect.) seasonality, length of fight, handling practices and length frequency of catch. Studies have found that release mortality is dependent upon several key factors, water temperature being one of the more important factors. It was determined that once water temperatures exceed striped bass’s optimum temperature range (70 degrees) that stress induced mortality increases dramatically. Air temperature is also an important factor. Research found that higher air temperatures increase release mortality. It was also found that release mortality increased significantly when there are large differences between water and air temperatures as well as the amount of time the fish is exposed to those temperatures. These findings indicate that mortality may increase significantly when fishing for striped bass during the summer months even if the water temperature are below 70 or if the fish are coming from deeper/cooler waters. Some states such as Maryland in particular have put together an advisory notices that caution anglers from fishing for striped bass when conditions result in elevated release mortality. Maryland has stated that recreational dead discards is the most pressing problem for the Chesapeake Bay striped bass population and advises anglers not to target striped bass when air temperatures result in excessive high discard mortality.
Recreational anglers, for the most part, understand that the style of hook and the location where the fish is hooked, have a significant impact on the survival rate of a released fish. Gut hooked, gill hooked and deep hooked fish display a discard mortality rate 6 times higher than fish hooked in the jaw or lip. Circle hooks, as defined as “a non-offset hook where the point is pointed perpendicularly back towards the shank”, have been demonstrated to drastically reduce the rate of gut or deep hooked fish when fishing with live and cut bait. States need to adopt mandatory circle hook regulations when fishing with bait.
The stress of fighting and landing a striped bass is another important factor that can result in elevated angler induced mortality on release striped bass. When fish struggle intensely for a prolonged period of time, lactic acid buildings up in the fish’s tissue leading to acidosis which can cause physiological imbalances, muscle failure and death. This type of mortality is not always immediately seen and a fish that appears to swim away after being released may not resume its normal behavior, its feeding patterns may become disrupted, may become more vulnerable to predation and the fish’s ability to fight off parasites and diseases and heal from wounds becomes compromised. Based on a wide array of research, a fish that is landed quickly has a better chance of survival after release than one subjected to a prolonged fight. States should consider advising anglers against using inappropriate-sized gear such as light tackle outfits designed for smaller species of fish and fly tackle when targeting striped bass due to its increased mortality on released fish.
While managers and fishermen understand what causes elevated discard mortality rates, what is not discussed in Addendum VI is the vast scale and the number of individual striped bass that are released each year. According to NOAA Fisheries, over 90% of all striped bass caught by recreational anglers are released. In numbers of fish, that amounts to 33.2 million striped bass in 2018. There has been a growing culture within the recreational striped bass fishery that catch and release demonstrates ones commitment to this species long-term sustainability. This culture also tends to cast shame on anglers that opt to land a legal sized fish to eat. This is consistent with the trend to push the striped bass fishery more towards a sport fishery and away from a consumptive fishery. As outlined above, catch and release does not come without consequences when discard mortality values are applied. Even the fisherman who employees an entirely catch and release philosophy with striped bass must have some discipline, restraint and self acknowledgment that their net mortality on the striped bass population, despite not keeping any fish, may far exceed the causal angler who lands a few striped bass per year to eat.
Managers also need to acknowledge that striped bass have been responding to warming shelf water by moving into deeper, more northern and eastern waters. These are areas that may not have been traditionally sampled for striped bass. Furthermore, there is no directed fishery for striped bass in federal waters and thereby our understanding of this distribution shift to cooler waters is limited. This lack of information also results in a presumed underestimation of older female striped bass in the assessment. Surveys need to be adjusted to account for more fish being in deeper, cooler waters of the EEZ. More striped bass are also being observed in Canadian waters and it is unclear how or if these fish are being incorporated into the assessment. Resources need to be made available to support research and tagging programs to investigate this trend and to determine what impact this is having on our ability to accurately assess the fishery.
With Addendum VI moving forward and public hearings scheduled for early fall, RFA believes it is important for fishermen to understand the facts within this fishery. Based on the current status of the stock and where it has been, the Atlantic Striped Bass population is not facing an imminent conservation problem but a management problem that can be addressed with minor changes. In fact, reduced effort in the 2018 ocean striped bass fishery and all other fisheries, based on NOAA Fisheries MRIP estimates, resulted in a 18% reduction in total removals of striped bass which is the goal of Addendum VI. This demonstrates that drastic changes to recreational regulations may not be needed at this time. Greater protection should be placed on pre-spawn fish, particularly in spawning areas such as the Hudson River and other north east coast tributaries which have proven to host successful spawning. Managers should avoid measures that focus solely on increasing the minimum size limit. Higher minimum size limits focus harvest mortality entirely on larger, more reproductively valuable fish while driving up dead discards. Higher minimum size limits also exclude a large faction of the recreational sector that prefers to harvest striped bass for food. The net mortality from these consumptive fishermen, in many cases, can be lower than a fisherman who only catches and releases striped bass when discard mortality is factored. States need to implement strong circle hook regulations and other measures to reduce recreational discard mortality such as following the model set forth by Maryland which issues advisories to anglers cautioning against targeting striped bass when water and air temperatures exceed certain values that elevate discard mortality. More research and resources is needed to assess the movement of the striped bass population into non-traditional areas in response to changes in environmental conditions as well as new spawning areas as water quality has improved and obstruction removed.
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