Despoiled seas

Market hunting has been prohibited in the United States for more than 100 years, and today we tend to look aghast at the practice that exterminated the passenger pigeon while bringing many other species to the brink of destruction. Before the passage of the Lacy Act and other conservation measures at the beginning of the 20th century, it appeared that the United States would soon be bereft of wildlife, especially those forms that appealed to the human palate. But attitudes changed and laws were passed, allowing the recovery of many species.

Imagine, however, an alternative history, one in which the conservation movement of the progressive era had been stillborn and market hunting continued to be regarded as an efficient means of delivering cheap and tasty protein to the urban masses. In such a scenario, as waterfowl grew increasingly scarce, hunters would have abandoned their shotguns in favor of ever larger nets that could scoop up every manner of flying creature. As ducks and geese disappeared, the market would have turned to coots and blackbirds, finally settling on dragonflies and other insects. Ultimately, the hunting nets would have become powerful enough to rip up the muck of the marshlands, destroying the very habitat that sustained the commercial enterprise in the first place.

Farfetched as it may seem, these same processes are essentially being played out in marine habitats across the planet. The destruction of oceanic life, thoroughly and incisively chronicled by Callum Roberts, a marine conservation biologist at the University of York, in The Unnatural History of the Sea makes a grim and a compelling tale. Chapter after chapter documents one extinguished fishery after another, culminating with a depiction of the industrial-scale deep-sea trawlers that scrape the ocean bottom clean of most macroscopic organisms, obliterating complex ecosystems based on slow-growing sessile invertebrates. If current trends continue, Roberts warns, the end result could be radically impoverished marine communities dominated by jellyfish and other relatively simple forms of life. Roberts’s warning is perhaps exaggerated, but not necessarily by much.

Humanity’s relative disregard for oceanic environments is clearly evident in statistics. “Twelve percent of the world’s land,” Roberts informs us, “is now contained in protected areas, whereas the corresponding figure for the sea is but three-fifths of 1 percent.” This seeming indifference, however, does not necessarily reflect public sentiment; surveys in Britain and the United States show not only high levels of support for marine reserves but also disappointment that so few waters are actually protected. By such a reading, only the power of the fishing industry, coupled with the reluctance of fishery scientists and managers to admit their failures, have prevented us from making the same progress in the water that we have on the land. But it also seems true that certain broad attitudes toward the sea remain distinctively lax, thwarting reform efforts; “We still view it,” Roberts writes, “as a place where people and nations should be free to come and go at will, as well as somewhere that should be free for us to exploit.” A deeper factor may be our stubborn reluctance to acknowledge aquatic animals as animals. In U.S. national parks, where hunting is unthinkable, fishing often seems to be encouraged. For centuries, Christian doctrine prohibited the eating of meat—defined as the edible flesh of an animal—on Fridays and during Lent, thus necessitating the consumption of fish, apparently an oddly mobile form of vegetable life.

In Roberts’s account, the origins of intensive fishing can be traced in part to medieval Christianity’s prohibitions on mammal and bird eating, which could cover up to 180 days of the year. As northern Europe’s population expanded around the beginning of the second millennium, inland fisheries could no longer yield adequate supplies, thus requiring a turn to the sea. In Britain, both archeological and historical evidence shows an 11th-century transition to saltwater fish, a previously little-used resource. In a story that would be often repeated, early bounties in Britannic waters eventually faltered, forcing local fishermen to make greater efforts and to travel to ever more distant fishing grounds to reap the same harvests.

After detailing Britain’s medieval fisheries transition, Roberts takes his readers on a historically and geographically structured exploration of the global misuse of maritime life. Some chapters focus on specific places, including the Caribbean Sea and Chesapeake Bay, others on specific forms of life, such as codfish and whales, and still others on specific fishing techniques and the controversies that they generate, particularly trawling. Constants throughout these chapters include the turn to new species as earlier stocks are exhausted, the development of new technologies that allow larger hauls and the exploitation of previously inaccessible environments, and the continual search for new fishing grounds. By the late 20th century, all three techniques had essentially been played out, resulting at long last in a declining global catch.

Laissez-faire rules

The despoliation of the seas, as Roberts shows, was never unopposed. Some of the staunchest critics of new, more damaging forms of fishing were often fishermen invested in traditional methods. But although opponents of destructive fishing often found some government relief in earlier periods, the laissez-faire attitudes of the 19th century loosened both traditional and legal constraints. A landmark British royal commission of 1863 concluded that fishery regulations, even for the most detrimental forms of bottom trawling, were simply not necessary. At the time, the sea was commonly viewed as inexhaustible, while pseudo-scientific theories held that trawling actually enhanced oceanic productivity by “cultivating” the sea floor. Economic theory, moreover, maintained that fishing for any particular species would fall off as stocks became rare, thus allowing recovery without government intervention.

All such notions supporting a hands-off approach to marine food resources were eventually discredited, but not before vast damage had been done. Moreover, the theoretical models subsequently developed by fishery specialists have not proved adequate to the task of conserving what is left. Not only do state ministers often ignore the advice of specialists in order to placate commercial fishing interests, but some of the foundational models of fisheries science appear to be faulty. Maximum sustainable yield is often thought to be obtainable by reducing a natural fish stock’s size by up to 70%, which results in large numbers of young, fast-growing animals. Roberts counters that older, slow-growing individuals often produce the large batches of eggs that are necessary for successful long-term reproduction. More significant is the phenomenon that Roberts dubs the “declining baseline.” What have been regarded as the pre-exploitation baseline populations of many of the most economically important fish species, he argues, were actually already vastly reduced from those of earlier times. The pristine abundance of the seas, Roberts continually reminds us, was often so great as to be scarcely believable by modern observers.

Roberts further criticizes fishery science for its managerial focus on single species, ignoring the complex ecological interactions that are not easily captured in even the most complex mathematical models. Such interactions sometimes mean that an exhausted fishery cannot recover even if fishing ceases entirely, because new species can move in to occupy the niche of the previously targeted animal. In many circumstances, invertebrates gain as fish species are reduced or eliminated.

Reserves to the rescue?

For all of its horror stories of mindless greed, reckless policy, and intellectual blindness, The Unnatural History of the Sea is not a pessimistic book. The solution to the plight of the oceans, Roberts persuasively argues, is ultimately rather simple. What is necessary is a comprehensive system of marine reserves, covering roughly 30% of the aquatic environment, in which all exploitation is banned. Such a system of reserves would not only allow the eventual recovery of the sea’s natural diversity and abundance of life, but would also create restocking zones for adjacent areas open to fishing. The result, he contends, would be truly sustainable, as well as much more easily gathered, marine harvests. Roberts’s approach is ultimately pragmatic, concerned both with maintaining fisheries and preserving fish and other forms of oceanic life. He is even willing to allow many of the most intensive, industrially oriented forms of fishing, so long as they are adequately regulated and spatially constrained.

The Unnatural History of the Sea is a well-written, carefully researched book that should be widely read by those interested in environmental history, fisheries, the marine environment, and global ecological preservation. More important, Roberts’s recommendations should be taken seriously by everyone concerned with the regulation of marine resources. But that said, it is important to note that this is not necessarily an easy book to read; the stories of destruction are so ugly and relentless as to be emotionally exhausting, forcing this reviewer to digest it in small doses. Only at the end, when Roberts examines successful contemporary reserves, does his underlying optimism emerge. Perhaps a few more stories of effective preservation would have made The Unnatural History of the Sea more accessible to a broad audience.

My other criticisms of the book are equally minor. Roberts virtually ignores the possible deleterious effects of global warming on oceanic environments, although inclusion would admittedly have made an already grim book all the more depressing. I was also disappointed by Roberts’s unduly Eurocentric historical perspective, which ignores the long history of intensive fishing in other parts of the world. Roberts acknowledges this deficiency in his preface, attributing it to the lack of available sources. In the case of Japan, however, a number of English-language works are available that he could have profitably referenced.

But one can never expect an author to cover any subject exhaustively, and Roberts must be credited with crafting what is simultaneously a fine history and natural history of a most unnaturally destructive process. His recommendations regarding the creation of a comprehensive system of marine reserves, moreover, could serve as a blueprint for a genuinely successful program of marine conservation and preservation. Earth’s vast marine expanse is indeed in deep trouble, and The Unnatural History of the Sea provides a much-needed wake-up call.