Lee M. Talbot
In part IV the authors examine the status of marine conservation, ecology, and management, analyzing the causes of present problems and examining what is being done to address the situation. The world's marine habitats have been significantly altered; marine living resources have been depleted by overexploitation, pollution, and conversion of estuarine habitats. Until recently, even among many scientists, the conventional wisdom was that the oceans and the marine resources were so vast that human activities could not greatly affect them. There are still many marine scientists and managers who downplay overfishing and who continue to apply and teach the scientifically discredited, simplistic approaches to fisheries management that have led to the depletion of stock after stock throughout the world's oceans.
However, new research has shown that human activities have profoundly impacted many of the world's marine ecosystems. Around 90% of the world's larger predatory fish already have been lost to overfishing, with significant and, in some cases, probably irreversible changes to their ecosystems. Further research is demonstrating that for whales and other forms of exploited marine living resources, the original population levels appear to have been very much higher than previously assumed. This means that the present populations represent severe depletion, even though they are being managed as if they were at healthy levels, with no signs of overexploitation.
In chapter 12, Sidney J. Holt analyzes the idea—fundamental to most marine exploitation to date—that extractive use of “renewable” living resources can be sustained by imposing simple management measures. He first reviews the history of the analyses and models developed to describe the reproductive behavior of marine living resources in relation to exploitation. Many of these were deterministic models; they led to the development of the concept of maximum sustainable yield (MSY), an approach to fisheries management that is still dominant even though it has been discredited scientifically for many years.
The deterministic models, such as MSY, predict reversible changes from one steady-state condition to another. They are based on the idea that the ecosystem is stable and unchanging, and they focus on a single species, ignoring the multiple interactions with the other species in the system. As such, they have little relationship with the real world.
Holt describes the origins of “the power of the otherwise disreputable MSY,” showing that it came from the insistence in 1958 by the United States that MSY be accepted as the (p.182) internationally acceptable reference point for management. This insistence was based on political considerations aimed at protecting the economically valuable U.S. fisheries from foreign exploitation.
Holt also addresses the question of sustainability. For a fundamental problem with the way sustainability is used is the question of the time frame: “How long is sustainable? In perpetuity? For a fish or human generation? Or two or three?” Holt notes that the matter of the time frame is “rarely mentioned explicitly and practically never discussed in depth,” yet how to deal with variations through time is a core problem in efforts to manage for sustainability. Natural intrinsic population cycles can be very long (perhaps a century or more), yet the time period considered for a management regime is generally much shorter. Consequently Holt emphasizes that “the notion of sustainability is essentially meaningless except within a specified and appropriate time frame.” And he notes the confusion between biological sustainability and economic sustainability. A biologically sustainable harvest might well be too low to be economically sustainable, and conversely, within a fixed time period, an economically sustainable harvest could lead to extermination of the resource.
Holt concludes by discussing problems of the current approaches to multispecies management and ecosystem management. Because of the complexity of the ecosystems and the limitations of knowledge, these approaches also suffer from a simplistic approach. He states that an ecosystem approach can be perverted to justify unsustainable exploitation of some of its parts; for example, proposed overfishing of some large predators in order to “save” the prey, or to regain a “balance.” And he determines that “the economic and social forces favoring unsustainability are alive and kicking and looking for loopholes in the scientifically based conservation matrix.”
John R. Twiss Jr., Robert J. Hofman, and John E. Reynolds III focus in chapter 13 on the U.S. Marine Mammal Commission, the principles of marine mammal management and conservation associated with it, and the status and conservation issues involved with varying groups of marine mammals. The authors’ approach is to show that much of the past several decades’ history of marine mammal conservation “is reflected in the background, content, and implementation of, and changes to, the U.S. Marine Mammal Protection Act (MMPA).”
The MMPA is one of a series of U.S. environmental laws passed in the early 1970s. At that time, there were a number of highly publicized incidents of abuses of marine mammals: hundreds of thousands of dolphins were killed in the tuna fishery, the International Whaling Commission failed to stop the decline of the great whales, and baby seals were killed on the Canadian ice floes. The public reaction was strong, and members of Congress said that during this period they received more mail on marine mammal conservation than on any other issue save the Vietnam War. This, and other factors described by Twiss, Hofman, and Reynolds, led to passage of the act.
The MMPA was particularly significant for a number of reasons, including a series of firsts in resource management legislation. For example, it was the first act to mandate an ecosystem approach, the first to establish the precautionary principle (now established in national and international law), and the first to require optimum sustainable populations.
The authors detail the key provisions of the MMPA, including the functions and composition of the Marine Mammal Commission and its Committee of Scientific Advisors, both of which the act established. They then discuss how the optimum sustainable population determinations evolved, and they detail how the ecosystem approach to marine conservation was developed. Several amendments were made to the MMPA; the authors examine their origins, (p.183) significance, and effects. The Marine Mammal Commission's important role in a number of international marine mammal conservation issues is also considered. For example, the authors write at length about the commission's involvement with the International Whaling Commission and the negotiations leading to the Convention for the Conservation of Antarctic Marine Living Resources.
After providing a broad overview of past and current marine mammal conservation issues and the steps taken to address them, Twiss, Hofman, and Reynolds point out that conservation must be a “dynamic process” that takes into account both socioeconomic and biological-ecological factors. They emphasize that the public, the scientific community, environmental and industry groups, Congress, and the courts all play important interacting roles in marine conservation.
In addition to a number of areas where marine mammal conservation has been effectively achieved, the authors address the issues that have resisted solutions, and the new, previously unrecognized, and sometimes controversial issues that have arisen. One of the key attributes of the Marine Mammal Commission, they note, is its “ability to look forward and attempt to proactively address issues before they reach the crisis stage.” Looking ahead, the authors state that the issues judged to be the most pressing in the near future are the “direct and indirect effects of fisheries, environmental contaminants, harmful algal blooms, disease, underwater noise, habitat degradation and destruction, climate change, difficulty identifying optimal management units, and ineffective management strategies.”
In chapter 14, Michael L. Weber focuses on the ideologies that underlie and play a major role in determining the policies of government, management, and even science. Weber defines ideology as “the body of doctrines, myths, and beliefs that guides an individual, social movement, institution, class or large group.” He considers that it includes a mixture of myth and fact that guides how we view the world and make decisions.
Prior to the 1970s the policies for marine wildlife were dominated by an ideology of abundance. Weber believes that the passage of the MMPA introduced a counterideology, the ideology of scarcity.
The ideology of abundance has a long history for marine species. It reflected a conviction that humans could manipulate nature to provide maximum use of resources, and that unused resources were wasted resources. A major effect of the ideology of abundance was to remove the need for caution. For example, believing in abundance, and thinking that the fishing yield was only limited by the capacity of the fishers, until the late 1980s the U.S. government had as a principal goal the expansion of the U.S. fishing fleet. With this approach, it followed that there was greater danger of underexploiting fish than overexploiting them, so the burden of proof was on those who urged conservation.
Weber describes the factors that led to the passage of the MMPA, with its underlying ideology of scarcity. But he also describes the continuation and hardening of the ideology of abundance in the fishing industry, and the subsequent passage of the Fishery Conservation and Management Act in 1976. This led to a vast increase in the U.S. fishing boat fleet and, by the late 1980s, to the decline, through overfishing, of many fish stocks, which Weber notes emphasized how wrong our earlier views were about the potential impacts of fishing. In reaction, reform efforts reflecting the ideology of scarcity led to passage of the Sustainable Fisheries Act of 1996. The author discusses the developments since then and contends that there are significant challenges ahead before the ideology of scarcity really overcomes the practitioners of the ideology of abundance. (p.184)