The Double-Crested Cormorant: Symbol of Ecological Conflict

7. Fishing America’s “Fifth Coast"

7  Fishing America’s “Fifth Coast” the dodgy conflicts in which double-crested cormorants ‹nd themselves involved time after time revolve around food, and food to them means ‹sh. Although cormorants sit at the top of their food chain as aquatic predators, adult trout and salmon and some other ‹sh do the same job. As top predators along with man, these ‹sh and the doublecrested cormorants face a tangle of obstacles and changes that complicate the overall food chain in ways scientists and ‹shermen may never fully understand. But the common factor in this jumbled food chain scenario is the ‹sh. Humans, of course, always had food options other than ‹sh, but as in the case of early European settlers, the plentiful ‹sh stocks often became the mainstay of their diets. Along the lakes and their tributaries, humans always had the options of raising crops and tending livestock and frequently lived directly off the wild bounties of the land; they could live without ‹sh. The cormorants, salmon, and trout had no other choices. Their environmental niche was in or on the lakes, feeding on ‹sh, and the only other alternative was their extinction. In a signi‹cant sense, then, since no species exists in a vacuum, the story of the cormorant’s history on the lakes is the history of the ‹sh and the ‹shermen. Without understanding the role of sport‹shing and its big brother, the commercial ‹shery, it is impractical to attempt to understand the cormorant’s second coming and present niche on the lakes. The birth of what Samuel de Champlain referred to the “sweet seas,” mers douce, the Great Lakes, is a relatively recent occurrence on 80 the geological calendar. The period of ten to twelve thousand years ago corresponds to something like the time in the past when you began reading this sentence. It is essentially now. And the extreme infancy of the Great Lakes shows itself in the very few kinds of ‹sh found in them. The vast expanse of more than 5,400 cubic miles of freshwater boasts only 136 to 150 different ‹sh species, depending on the data source and classi‹cation scheme. In the dozen or so millennia that mark the history of the lakes only 150 species at most have had enough time to call the Great Lakes home. Even accepting the dif‹culty of comparing other water systems to the largest freshwater system on Earth, many other freshwater basins support far more ‹sh species than North America ’s inland seas. According to the website Fishbase.org, an online relational database of ‹sh species developed through collaboration with the United Nations, the European Commission, and nine research institutions , our own Mississippi River basin claims 226 ‹sh species. South America’s massive Amazon sustains 1,214 and the Orinoco River basin 540 distinct species of ‹sh. The site also lists Vietnam’s Mekong River as having 785 species. And again, the vast waters of the Great Lakes come in with only 150. In the comparisons, if we allow an adjustment for a greater diversity of life occurring in tropical climates, 150 species is still a meager showing. Numerous studies of the ecosystems of the Mississippi, Amazon, Orinoco, and Mekong reveal how fragile their food chains are, and with as much as an order of magnitude of difference in the number of species, it’s easy to imagine how tenuous the relationships are among the relatively few species of the Great Lakes. And it is just as simple to imagine how easy it would be to upset their still-evolving natural balance . And what could upend that balance more than humans removing so much high-quality protein from the ecosystem in the form of predators like trout and salmon. And all that bounty, unregulated, and free for the taking? Throughout the literature on the early exploration of the lakes, North America’s Fifth Coast, writers recorded an almost unbelievable abundance of ‹sh. The numbers were uncountable. And the sizes! The extent of the ‹sh populations was unlike anything Europeans had seen in their homelands. Tons and tons of forage-sized ‹sh and huge prowling monsters such as the primitive-looking, long-lived lake sturgeon, measuring nine feet long and weighing-in at close to four hundred Fishing America’s “Fifth Coast” • 81 pounds. It takes years of growth for sturgeon to achieve such proportions , the price for their size being...