(Painting by Barry Kent MacKay)
To understand why cormorants cannot eliminate fish, one must have at least a very elementary understanding of how all creatures exist. Put simply, we all need to have food that can be converted by our bodies into tissue, energy and warmth. This conversion process is called metabolism, and is a two-part process. Food provides us with the means to create cells and tissues and organs and fats. But the energy we expand in order to acquire food consumes our physical being.
Put simply, what we use up in producing energy and body mass must be balanced by what we consume. If we eat more than we need we grow fat, if we consume less than we need we grow thin. If we continue to eat less than we need we not only become thinner, we ultimately sicken and die.
Matter, heat and energy are interchangeable. The energy that goes into the building and maintenance of healthy bodies, to keeping us warm and allowing us to move, derives from the food we eat. The energy that it takes to read these words is much less than it takes to run a marathon or work out at the gym, but whatever we do, we have to be sure that we have the fuel with which to do it. Even sleep takes some degree of energy.
But there is one massive difference between us, and all other species. That difference is technology. We don’t use very much of our own metabolic energy to obtain food. Instead, we use energy derived from other sources. The food a deer consumes must provide all the deer’s needs, from what is required to grow and maintain its body and bodily functions, to the energy it takes to search for food, avoid predators, breed, keep warm in cold weather, find shade or cover, or anything and everything else it does as a function of being and staying alive. The wolf who hunts the deer has the same limitations. The energy spent obtaining food must be balanced by the energy derived from the food.
Now consider the human in pursuit of the same food as the wolf. He too uses energy — to drive to the hunt site, to climb to his deer stand, to load his gun, to squeeze the trigger — but all of this is made possible by energy sources that do not come from his body, but from fossil fuels, from hydroelectric power, or perhaps from other energy sources that exist independently of what he derived from his food. Enormous amounts of energy that have nothing to do with his body’s metabolism, and may be generated and spent thousands of miles away, are required to put him in a position where, with the squeeze of a finger, he can kill a deer, and if he does not, no matter — technology provides him with other food sources.
A few wildlife species have learned to use the most simplistic tools — a small bird found only in the Galapagos Islands can use a stick to probe for insects, for instance, and so can a species of crow found on New Caledonia, and so can the chimpanzee — but not one other species has access to complex tools and the outside energy sources it takes to provide them. A fisherman without a boat and engine, a synthetic rod and reel, perhaps a fish finder, and don’t forget clothing, a cooler, a wristwatch, a car, a choice of hooks and lures, a landing net, perhaps eyeglasses — countless mechanically produced aids whose presence cost him no caloric output — uses far more energy than the energy he derives from the fish he catches and consumes.
The cook may give little thought to the energy that manufactured the can he opens in order to access the soup he is preparing for lunch, not to mention the energy expended by farm machinery to grow the vegetables in the soup, nor to build and run the machinery that moves those vegetables to the factory where more machinery built and using more energy prepares the ingredients to go into cans built and transported.
That transportation uses still more machinery, said machinery representing still more energy both to be made and to function in order to bring the various components together at the factory. Then more energy is required to ship the products in containers that used still more energy to be made and transport