The recent declaration that striped bass stocks will be recovered as of Jan. 1, 1995, is a landmark event that caps a 10-year restoration from a point in 1984 when the stock was declared to be at the lowest level ever recorded. The announcement of good reproduction this year following a record year in 1993 reinforces this declaration. It has been a miraculous turnaround that in hindsight can be attributed to the application of three principles:
1 – fisheries management is an essential complement to habitat management for maintaining fish populations;
2 – fisheries management must be coordinated throughout the range of a fish stock to be effective; and
3 – fishery science must play a central role for fisheries management to be effective.
These three principles transcend parochial fisheries debates and serve as a general formula that should be applied to other species in need, such as weakfish, bluefish, American shad, and summer flounder.
Resolving the debate between overfishing and pollution was essential to the striped bass recovery. While many scientists in the early 1980s believed that fishing pressure was excessive, there was also evidence of water quality problems on the spawning grounds. The many efforts to sort out these factors led to an important realization best expressed in a 1985 analysis by Dr. Phil Goodyear which concluded:
“The results indicate that the observed downward trend in the Chesapeake Bay population can be halted or reversed by a reduction in fishing mortality, even if contaminant toxicity is the proximate cause for the decline.”
This realization laid the groundwork for the restoration effort by highlighting the importance of fisheries management as a complement to habitat management.
A second debate which had hampered states’ ability to take action on striped bass was the regional bickering over who was most responsible for overfishing this migratory stock. Chesapeake fishermen blamed northerners for catching large spawners, and New Englanders railed against the Bay harvest of immature fish. Congress grew impatient with this stalemate and in 1984 passed the Atlantic Striped Bass Conservation Act which compelled all states to implement the fishery management plan of the Atlantic States Marine Fisheries Commission (ASMFC). Thus, the concept that striped bass should be managed consistently throughout its range was now embodied in law.
Finally, stimulated by the Maryland moratorium, the ASMFC amended its management plan in 1985 to protect striped bass until they reached spawning age. This meant that specific fishing regulations during the restoration period depended directly on scientific analysis of growth and maturation rates. Work was also begun on a new plan that established rules for striped bass fishing based on “fishing mortality,” a mathematical term which describes the rate of fishing. Under this approach, in place since 1990, states’ management measures were annually assessed against rigorous scientific criteria. Never before had a coastal fisheries management plan been designed so completely around science.
Simply stated, the formula for the striped bass recovery was the control of fishing within limits prescribed by science and applied consistently throughout the range of the stock.
Recent experiences with other species reinforce the lessons learned from striped bass and suggest that a broader application of the same formula could enhance these depleted populations.
During the last decade Atlantic coastal stocks of weakfish (gray trout) followed the same pattern of decline as striped bass did a decade earlier. Management was driven more by politics than science and was not consistent coastwide. In response to the decline, the coastal management plan was amended, calling for reducing fishing mortality by 15 percent in 1992, 25 percent in 1993 and 1994, and 50 percent thereafter. Because of constituent pressure, no state fully complied with this schedule, and the stock has continued to decline. The latest stock assessment describes weakfish as “severely overfished” with the spawning stock now at only 2–3 percent of the maximum (20 percent is necessary for recovery). As a result it is now believed that an 82 percent reduction in fishing mortality will be necessary.
Bluefish have also declined dramatically in the last decade. The coastwide recreational catch dropped 70 percent from 1983 through 1992. This trend is reflected in the spawning stock, which declined from 300 million pounds in 1982 to 81 million pounds in 1989. Since 1989, fishing mortality has continued to increase and is now approximately double the target level. The principal management measure in the coastal bluefish plan, a 10-fish creel limit for recreational anglers, has not been uniformly implemented by member states. Scientists increasingly believe this stock to be overfished and may soon recommend further catch restrictions.
The decline of American shad in the Chesapeake Bay began two to three decades ago. There is virtually no sportfishery for shad now, and moratoria on commercial fishing are in place in both Maryland and Virginia waters of the Bay. The coastal management plan recognizes individual river populations and lists recommended fishing rates for each, but adherence to these rates has been inconsistent. The plan also recognizes the priority rights of the traditional fisheries in the rivers of origin and discourages ocean fisheries that intercept migrating shad. Despite this recommendation, most ASMFC member states still allow ocean harvests. Recent analysis has corroborated concerns that ocean fisheries target a mixture of healthy and depleted populations. Under these circumstances it is impossible to protect severely depleted populations like those from the Chesapeake.
Summer flounder, a highly valuable species to both commercial and recreational fishermen, were subjected to very high fishing mortalities during the last decade peaking in 1988–89 at about five times the overfishing level. The size of the flounder spawning stock set a record low in 1989. These developments combined with a sharp drop in flounder catches led to the adoption of new controls on fishing under the coastal management plan. A series of management measures designed to lower fishing mortality over several years was recommended and, in this case, was widely implemented. As a result fishing mortality dropped to the target level the first year, and the spawning stock appears to be recovering. The outlook is good for rebuilding the summer flounder fishery provided fishing mortalities are maintained at target levels.
The recent history of these four species illustrates a need for effective fisheries management similar to the need exhibited by striped bass a decade ago. All four cases display a pattern of fishing pressure growing until it becomes excessive, a slow response from management agencies, dramatic declines in stocks and substantial losses to the fisheries. Chesapeake Bay fisheries management has historically been politically driven. Science has taken a back seat to the desires of constituent fishermen. Fisheries decisions typically have been stalled first by reluctance to act until an obvious crisis, and second by disagreement over whether the cause of a given fish stock decline was overfishing, pollution or natural cycles, all of which influence Chesapeake Bay stocks.
Separating the influences of fishing, habitat and natural cycles is a challenge, especially for a temperate estuary like the Chesapeake Bay. However, the occurrence of declines in all four of these species at the same time minimizes the likelihood of natural cycles as a causative factor. These species also have differing estuarine habitat needs and use these habitats at different times of the year. While losses of some of their habitats have occurred, it is highly unlikely that habitat loss sufficient to cause the declines in all four species occurred simultaneously during the last decade. Furthermore, striped bass, which require many of the same habitats, have dramatically increased in abundance during this period. The lesson learned from striped bass is that fisheries management can restore and maintain stable fish populations in the short term while habitat losses are recovered in the long term.
The striped bass lesson that management should be consistent throughout the range of a stock is also reflected in these four case histories. In the case of bluefish and weakfish, partial adoption of management plan recommendations by individual states did not reverse declines in those species. The experience with Chesapeake stocks of American shad clearly demonstrate this problem. Maryland has had a moratorium on the harvest of shad in place since 1980, yet harvest has continued along the coast, and the stocks have not rebounded. Congress recognized this problem and recently passed the Atlantic Coastal Fisheries Cooperative Management Act which compels states to comply with all coastal fishery plans in the same way the 1984 legislation did for striped bass. As this law takes effect, the problem of inconsistent coastal management should be resolved.
The four examples here also demonstrate the ability of science to assess stock condition, document declines and prescribe corrective measures. Scientists documented excessive fishing mortalities and declining spawning stock for weakfish. Precise recommendations for harvest control were not widely implemented, and the stock declined further. In the case of summer flounder a science–based prescription for management is being implemented, and there are encouraging signs of stock recovery. Analyses of spawning stock size, reproductive success and fishing mortality as well as other techniques can provide reliable criteria for managing fisheries.
The recovery of striped bass stocks during the last 10 years documents the importance of fisheries management as a complement to other Bay restoration activities. Before the striped bass recovery, state level fisheries management inevitably stalled on disagreements about the conditions of stocks and the causes of those conditions. The striped bass experience clearly transcends these disputes by demonstrating the effectiveness of management that controls fishing within limits prescribed by science and applied throughout the range of a fish stock. The recent management histories of weakfish, bluefish, American shad and summer flounder also advance this formula and suggest that it be applied to other species.