APRIL 21, 1997
SUBCOMMITTEE ON FISHERIES, WILDLIFE AND OCEANS
(from Jersey Coast Anglers Association - May 1997 Newspaper)
SUBJECT: Interactions of Striped Bass, Bluefish and Forage Species
Thomas P Fote
22 Cruiser Court
Toms River NJ 08753
PH 732-270 9102 Fax 732-506-6409
Jersey Coast Anglers Association would like to thank Congressman James Saxton for holding this field hearing on this important subject in New Jersey and Congressman Frank Pallone for attending this hearing. JCAA is aware that both Congressmen understand the importance of Ecosystem Management to the citizens of New Jersey.
This is a subject near and dear to my heart. The more I learn about fisheries management the more I realize that we can not manage interrelated species one at a time. We keep managing the marine environment species by species when we should be managing the Ecosystem. Ecosystem Management is looking at the interrelationship of species and managing those species by their interdependency on each other and other environmental factors. To me this means that every time we take an action that impacts one species, we need to consider the effect on all species. The marine environment is like a gigantic structure built with many supports. We can pull out one or two of these supports and pretend there is no effect, but the structure will have been weakened. Because the structure has many supports, it is able to sustain the loss of a few. Eventually, however, the stress of the continual undermining of more and more supports results in the collapse of the entire structure. Then people will point at the last support removed as the one that caused the collapse, but anyone with common sense knows the collapse was imminent as soon as we began removing the original supports.
In the marine environment, every species is a support for the entire ecosystem. We might be able to overfish one species without causing a dramatic change in others. However, once we begin to decimate the food stocks for species like striped bass or bluefish, we cannot help having a serious negative effect on that species total population. Some species are more adaptable and can find alternative forage sources to augment their diet. Striped bass and bluefish, as juveniles, feed on similar prey. Striped bass are opportunistic feeders. According to a NOAA technical study stomachs of adult stripers have been found to contain alewife, blueback herring, menhaden (locally called bunker), mumichogs, mullet, rock eels, shad, sculpin, silver hake, silversides, smelt, tomcod, weakfish, white perch, lobsters, crabs, shrimp, isopods, gammarid crustaceans, worms, squid, clams and mussels. Over the years, through personal experience, I have seen striped bass feeding on sand eels, American eels, winter flounder, and summer flounder. Striped bass as adults feed by sight, sound (vibrations) and smell. They will eat almost anything that swims in the ocean, bays and rivers. They eat their prey whole because they do not have cutting teeth. When we impact their basic diet, we may not see a dramatic decrease in striped bass population because they adapt by eating something else and have a more varied diet to choose from.
Bluefish, however, have very different feeding habits as adult fish. They are primarily sight feeders. According to the study, adult bluefish consume primarily live fish by eating them whole or by chopping them into pieces. Their feeding is triggered by moving prey. They normally eat menhaden, butterfish, mackerel, squid, mullet, and sand eels. We have seen a faster change in the bluefish population than with striped bass due to the decline of menhaden, squid, sand eels, herring, and butterfish. We can expect any decrease in their normal prey species to have a dramatic and quickly observable effect on the overall population and regional distribution of this species in particular.
When forage species were particularly prevalent in the 1970s, both predator species were eating the same abundant forage species. The abnormally high bluefish and strong striped bass populations during this time could be credited to the concurrent high population of sand eels and menhaden. Just to make the ecosystem point again, the high populations of sand eels are attributed to the collapse of the sea herring fishery in the 1970s because of the overharvesting by foreign fishing vessels. Sea herring are natural predators of sand eels in their larval stage. The population of menhaden rose significantly during the 1970s. This was due to a dramatic decrease in fishmeal production plants along the East Coast. Fishmeal demand dropped because of the increase in soy bean production. With the closing of fishmeal plants we saved the menhaden populations from overharvesting for a while.
Even though striped bass appear more adaptable and able to maintain their numbers over the short haul, if we continue to destroy their forage base, we will eventually see the same result as we have seen with bluefish. The striped bass, because of their ability to adaptable to a wider range of forage species, have a broader support system. Still, we can remove only so many of their supports before the fishery collapses. The problem will not be just the last action we take, but all of the actions we have taken cumulatively over the years.
The species that play important roles in the historical diets of both striped bass and bluefish are menhaden, sand eels, squid, mackerel, shad and river herring. In the last few years, we have seen a collapse in the population of sand eels due to a variety of causes that are difficult to pinpoint. We have seen a dramatic increase in the harvest of menhaden in the New Jersey bait fishery. In 1982, commercial harvesters landed 1,637,357 pounds of menhaden for use as bait. In 1995, New Jersey harvesters landed 36,567,357 pounds ostensibly for the same purpose. The change from 1982 to 1995 represents a 2,100 percent increase in removals. The preliminary numbers for 1996 indicate that processors in Cape May alone have shipped 46 million pounds, another massive increase, even over just 1995 landings. These huge increases in the New Jersey bait harvest represent only a portion of the bait harvest for the entire coast and does not take into account the hundreds of thousands of metric tons of menhaden being stripped from the ocean by commercial boats fishing for the fishmeal reduction industry. To add insult to injury, this bait is being used to fill the dramatically increasing number of crab traps along the East coast and Gulf of Mexico. So, as menhaden populations are decimated, so are the crab populations that striped bass feed on, leaving even fewer prey alternatives for this critically important and economically beneficial species.
In 1986, the squid fishery was very small due to low market demand and the lack of on-shore freezer facilities. Presently the commercial and recreational industries fear that squid stocks are on the verge of collapse because of overharvesting. NMFS has now declared sea herring and mackerel as "underutilized" species so we can safely predict that these species will approach collapse within the next five years. We must change this phony terminology since NMFS definition of "underutilized" is widely recognized as a death sentence for a species and more closely matches our definition of "on the way to extinction." I will not waste your time with a litany of NMFS failures in the underutilized species category but will simply mention bluefin tuna, sharks, whiting, tilefish, and monkfish. The point is that the historical staple dietary sources of striped bass and bluefish are under attack and will most assuredly damage these and other key predator species viability.
In the 1980s there were numerous articles blaming the collapse of the striped bass and weakfish stocks on the eating habits of bluefish. They were called the "piranhas of the ocean." Now, in the 1990s, we are calling the striped bass piranhas and blaming them for the decrease in the stocks of bluefish, river herring, shad, and crabs. Dr. Lionel Walford, Director of NMFS Sandy Hook Marine Laboratory, studied the rise and fall of striped bass and bluefish populations. His research did not find a correlation between the abundance of one species and the decline of the other species. Will it ever occur to us to blame ourselves?
Whenever I get into discussions about whether one species is responsible for the collapse of another, I am reminded of the article "This Was The Potomac River" by Frederick Tilp. He used the most meticulous records available from colonial times through the 1920s. He indicated that in 1932 the number of shad taken during a usual six week season was 22,500,000 fish. Under similar circumstances the amount of river herring taken was 750,000,000. The record striped bass haul for one seine haul at Sycamore Landing, VA in 1827 was 450 fish averaging 60 pounds. If striped bass are responsible for the decline of river herring and shad, how did they coexist in such abundance in the early 1800s with hungry 60 pound striped bass in their midst? Using sturgeon as an example of all fish in the Potomac, Mr. Tilp points out that in 1880, 288,000 pounds of sturgeon were landed. By 1890, 60,920 pounds were taken. In 1899, only 45,710 pounds were recorded and in 1976 only 170 pounds were harvested. In the 1990s, we are now discussing closing every sturgeon fishery along the East Coast and the American shad stocks are almost collapsed. Commercial greed and our own shortsighted management strategies are responsible for these and other management follies, not nature.
Nature provides balance very well on its own. It keeps the predator/prey relationship in check, but mans greed is the fly in the ointment. For example, look at the lemmings in Alaska. The lemmings go through a cycle that begins at a low number and stocks build through the years when the plants they feed on are in a cycle of abundance. As their stocks increase, the number of predators increase as well. When they become overabundant and overgraze their range, they march en masse into the ocean, drastically reducing their numbers. The following year, the predators, foxes, owls and others, produce fewer offspring. The stocks of both forage species and predators drop in unison and remain in harmony. It is easy to study lemmings because all the dramatic action takes place on land under the watchful eyes of scientists. As a key part of the food chain, changes in the lemming stock are dramatic and easy to observe. The reason I use this analogy is because menhaden, sea herring, mackerel, and butterfish do not reduce their numbers by committing mass suicide, however, humans have mass killing techniques such as purse seines, gill nets, and otter trawls that can accomplish the same results through overfishing, whether stocks are abundant or not. Our techniques have become so sophisticated that we have pushed many species to the brink of extinction.
In the ocean, the study of ecosystem management becomes much more complex. We cannot easily see the changes in stock in the same fashion that we observe changes in the number of lemmings, foxes and owls. For years, menhaden have been a major part of the striped bass and bluefish diet. There are studies to confirm this relationship. When we overharvest menhaden, other species like squid, sand eels and mackerel have historically made up the difference in the diets of striped bass and bluefish. The stocks of these species have now declined and have left few alternatives for supplementing the diet of striped bass and bluefish. For the last thirty years, NMFS has continued to declare some species, especially forage fish, as "underutilized." With the collapse of historical fisheries, many commercial fishermen have begun to harvest these "underutilized" species. There has been a dramatic increase in the harvest of bunker, herring, squid, ling and whiting. Some people do not consider ling and whiting as forage species, but bluefin tuna feed on them regularly. We are totally destroying the delicate ecological balance of nature by our unchecked overfishing and the result will be a dramatic shift in all predator/prey relationships in our oceans. We have seen what happens on land when we upset the balance of nature. Flooding, global warming, loss and contamination of potable water, extinction of species, and other man-made catastrophes all take place. When will we ever learn? It is my sincerest hope that the process will begin with this hearing today.
In looking at the available data and the natural history of bluefish and striped bass, clearly there is a paucity of data after 1980. Since the 1980s, we have spent and are continuing to spend millions of dollars on monitoring and modeling of striped bass. In comparison, only a small percentage of the money has been spent on collection of biological information. After 1980, fisheries research placed the emphasis on population analysis, a simple form of "bean counting." Now, with a reduction in available funds, scientists are directed toward using statistical modeling procedures as a cost saving method. They spend most of their time developing and maintaining these unproven population estimating techniques. Fisheries biologists today receive more training in statistics than in biology. Growing number of economists, statisticians and specialists in population dynamics are sitting on technical committees. Frequently the goal appears to be the development of statistics that look good on paper rather than reflecting what is occurring in the ecosystem. This hearing emphasizes forage species and their interrelationships. However, when we look at ecosystem management we must consider many areas. We must consider habitat loss, chemical contamination, physical change (dams, freshwater withdrawals for irrigation and drinking), and water quality. Without all the pieces to the puzzle, we can not understand the problem and thus never solve the problem.
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