Another winter is behind us, striped bass are showing up in Buzzards Bay and fishermen are starting to report first catches. This is the beginning of another fishing season in Massachusetts. Like many fishermen, I am looking forward to this season and hoping for familiar sights on the flats around Monomoy Islands where I fish most of the season. Soon, schools of 15 to 40-pound stripers ranging in number from ten to a couple hundred will arrive on these flats and stay until the middle of October. But although these fish seem plentiful, are they as healthy as those seen in this region years ago? The increasing numbers of stripers may lead us to believe that this fishery is strong, however, we should not forget that only 10 years ago, striped bass populations dwindled to record low levels due to poor management practices. This fishery suffered from both growths over fishing (fishing too small a fish for optimum yield) and recruitment over fishing (not allowing enough fish to successfully spawn). A recent upturn in the population viewed by fishermen throughout the coastal northeast has occurred only after the imposition of two moratoriums in the beginning of 1980's. These actions were implemented in two major spawning grounds of striped bass - Chesapeake Bay and the Hudson River. The Hudson River, the second largest estuary on the east coast is a major spawning ground for striped bass. Since data is scarce, it’s difficult to estimate recruitment (a survival rate measurement) in the Hudson River alone, but most scientist estimate that 30 to 40 percent of total striped bass population comes from this region. The striped bass spawning area in the Hudson River stretches approximately 60 miles from New York Harbor to West Point, New York. It is important to know that the actual spawning area of striped bass is fairly limited because they require a certain water salinity range (3 to 7 parts per thousand) to insure larval survival. In addition, the spawning area is limited due to pollution. Commercial harvest of striped bass has not occurred in the Hudson since 1976. At that time, the New York Department of Environmental Conservation issued a health warning against eating striped bass from this fishery because of elevated polychlorinated biphenyl (PCB) concentrations in their tissue. There is extensive industrial development along this waterway, and a large quantity of PCB’s had been discharged to the Hudson River from electrical equipment manufacturers. Though this is no longer the practice, these chemicals ("PCB" represents the acronym of more than 100 compounds) are very persistent in the environment with a high potential for accumulation resulting in increased cancer rates and other serious health issues for humans and other species. The discharges of PCB’s to the estuary resulted in concentrations of 5 to 10 times the U.S. Food and Drug Administration (FDA) action level of 2 ug/g in the fish tissue. The results of modeling conducted by scientists from Manhattan College indicated that under a no-action scenario, the average PCB concentration in the striped bass in the mid and lower estuary would decline below FDA level by 1995. However, the modeling exercise did not take into account that system supports two separate populations of striped bass: the resident population, which stays within the estuary system year round, and the migratory population, which visits it only for few weeks in the summer months. Recent data obtained by the New York State Department of Environment Conservation showed that the concentrations of PCB’s in tissue of 2- to 5 year old striped bass in the middle-lower estuary declined from 3.5 (1988) to about 1.6 ug/g (1996). These results represent an average value for all striped bass caught in middle-lower estuary. Recent discovery allowing separation between migratory and resident striper populations based on strontium to calcium ratio in the otolith (a lose head bone) brought another interesting twist to the PCB issue. The PCB concentrations in the resident population in the middle-upper estuary has been considerably higher and were consistently above the FDA action level than in those stripers that migrate to the ocean. Although decline of PCB concentrations in striped bass tissue is real, it appears to be still too early for commercial harvest, since the majority of caught fish will represent resident fish with significant human health risk. Additionally, the Hudson River basin, containing the most heavily populated urban center in the nation, has been subjected to other serious pollution contamination scenarios. Sewage and industrial chemical discharges have had a profoundly negative effect on this ecosystem. However, the construction of new industrial plants and the upgrading of wastewater treatment facilities markedly improved water quality in the middle-lower Hudson. In spite of successful pollution abatement programs, sediments in the lower estuary still show the remnants of severe industrial-related contaminant inputs, which have had a serious impact on the health of this system. Amazingly enough, a positive change has occurred in the Hudson River system and for the first time in fifty years, we have a chance to observe a great recovery of a major estuary. This recovery is in its infancy stage, and the system needs to be carefully monitored to understand, among other things, how this recovery has impacted the striped bass that travel in these waters. It would be dangerously premature to consider opening this estuary to the commercial harvest of striped bass. Despite the pollution issues, commercial fishing has continued in the Hudson River for Atlantic sturgeon and American shad. Harvests of both species have dwindled in recent years due to over fishing. In view of depleted stocks of sturgeon and shad, closure of this estuary to commercial fishing should be considered, allowing these species to recover while scientists monitor this ecosystem. Only after careful research leading to conclusive data should a change in commercial harvest of striped bass be considered. This recommendation is not as radical as it may sound. We know that parameters influencing recruitment of striped bass and other species, such us starvation of larval fish, predation on fry, competition with other species for food and space, natural climatic events and diseases has not varied significantly over these years. Additionally, we know that the water quality and purity of the bottom sediment improved systematically due to stringent EPA regulations. Both of these elements are very important not only for stripers, but for the functioning of the entire marine ecosystem. To fully comprehend significance of this recovery it is important to know the unique characteristics of striped bass. Based on laboratory studies we know that striped bass are a very sensitive species. Larvae and young fish can be easily affected by natural parameters like water temperature, pH, and dissolved oxygen. Additionally, striped bass do not begin to reproduce until they are 5 - 6 years old, much later than many other marine species. And finally, stripers migrate annually and during their journey are exposed to and can be susceptible to potentially toxic chemicals at various destination points. The sudden influx of pollutants, like ammonia, to which stripers are extremely susceptible, can potentially wipe out an entire young generation of stripers. In sum, it is miraculous that this fishery has recovered so well in such a short period of time. The introduction of a commercial harvest may very well destroy the recovery that has begun to occur. It is mandatory that any new management decisions be based in solid scientific information. The data currently available is quite limited and it would extremely careless to make any decisions before further analysis is conducted. Another key concern relates to reports of the increase catching frequency of undersized stripers. I encountered this scenario last summer when my client, Bill Uffner, caught a 44" striper that weighed less than 20 pounds (see enclose photo). After Bill’s catch, other clients caught a few fish in this range but all were healthy and their weight was proportional to their size. I did not make much of this isolated accident until fishermen throughout New England repeatedly asked me questions about undersized stripers. These fishermen were concerned because they were catching thinner fish more frequently than in previous years. Then I remembered a small article in the July 1998 issue at "On the Water" discussing the findings of The Atlantic Menhaden Advisory Committee. The Committee’s report revealed citations of diseased and malnourished striped bass in Chesapeake Bay and the depletion of menhaden stock, one of the main forage fish for striped bass. Additionally, the rate of menhaden’s recruitment seems to be declining as well. As with any species, the physical conditions of striped bass reflect the quality of the food they consume. Studies conducted by scientists from the University of Maryland indicated that since 1996, increasing numbers of striped bass females have been found in poor nutritional condition. The poor condition certainly adversely affects their chances for successful reproduction and makes them more vulnerable to diseases and effects of pollutants. Large cows, in order to be healthy, need to consume food containing high levels of fatty acids like sand eels and silversides as well as food of a lesser quality which can fill them up like herring or menhaden. When species lower in the food chain decline, the impacts can be seen further up through the food chain. This type of visible weakening within the food chain is an indicator of a serious crisis within the ecosystem. As fishermen and as conservationists, we should be concerned about the malnourished striped bass. Studies indicate that the greater the fish size the greater its fertility. The young spawning females (18-25') lay on a average only 14,000 eggs while those over 50 pounds lay 3.5 million. Since mouths of striped bass larvae do not form until they are 2-4 days old, their nourishment comes from a large yolk sack, with an attached oil globule. Eggs produced by females weighing 10 pounds or more have a greater probability of hatching than eggs produced by smaller females. Since they are larger and have greater yolk and oil reserves, larvae from larger females may be able to withstand food deprivation for longer periods of time. Small females that will reproduce with minimal success rate automatically replace the portion of large cows that are in poor nutritional condition and most likely will not reproduce. The spawning area for striped bass is relatively small. Females appear to return to their own natal areas to spawn. Despite their larger size, cows will forfeit their spawning territory if occupied by smaller females. The result is that the larger cows re-suspend their eggs and do not reproduce for that season. If this trend persists, population levels will decline because the recruitment from small fish is less and will not be able to sustain a striped bass population at current levels. Hence, the potential for disaster is real. Based on this information, we can develop a deeper appreciation for this species and understand why is so important that carefully researched fishery management practices be put into place. There is much to learn about striped bass, such as the size and structure of striped bass populations, the impact of hatchery-reared striped bass on the genetic variation of wild stocks, growth and mortality rates of larvae, or estimates of young-of-year recruitment, which represents the true abundance of juvenile fish. And our current management practices should be re-evaluated as well. Maybe we should try to better protect large cows because they represent the base for future populations. What is the impact of promoting the catching of trophy size stripers on the overall population growth? Also, the food source and its abundance in various regions along the Atlantic Coast should be evaluated in order to make sensible management decisions. And perhaps it is time to consider the adoption of uniform regulations in all areas where stripers are taken. Overall, we should treasure what we currently have for the next recovery may not come so easily.
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