"Talk after talk, northern seas to tropical jungles, the conclusions rang in accord, as with a gavel: Big predators were not just missing; they were sorely missed. It brought to mind a medical phenomenon haunting many amputees; the phantom pains of a missing limb. These top predators - these missing limbs - were still deeply felt."
The apex predators - big cats and bears, wolves and crocodilians, sharks and eagles - have long been a source of inspiration, wonder, and, yes, terror to our species. They've been venerated in our art, and folklore, displayed in our zoos and aquariums, sometimes treated as rivals or enemies, other times treated as gods or ancestors. But what do they mean in the greater scheme of things? How do they really fit into the natural world? Are they simply parasites living off of the suffering of their prey, or do they serve a greater purpose?
Wildlife journalist William Stolzenburg analyzes that question, and his answer is a definite vote for the essential role of apex predators. In Where the Wild Things Were, Stolzenburg travels the globe and meets with scientists to explore how predators don't just fit into their ecosystems, but how they shape them. Using examples as varied as the wolf of Yellowstone National Park to the starfish of a tidal pool in Puget's Sound, it is demonstrated that the presence of top predators benefits an ecosystem by keeping other species in check. Remove the predator and some prey species will flourish, but at the expense of others, out-competing them and possibly even driving their neighbors (and themselves) to local extinction. Similarly, removing a top predator can allow smaller, subordinate predators to explode in numbers, which in turn impacts the species that those animals prey upon.
Science isn't science without experimentation, and Stolzenburg is able to draw upon many case studies to support his position. Some are created in laboratory or controlled settings, sometimes under a microscope lens, sometimes in less-conventional surroundings (picture a college professor traveling several hours twice a month, just to throw some starfish - literally - out of his research pool and back into the sea). Others are the experiments that we create ourselves... albeit unintentionally. Consider, for example, Barro Colorado Island, created with the formation of the Panama Canal. In the absence of jaguar, harpy eagle, and other predators, some species were able to increase their numbers dramatically, and the forests are suffering as a result.
Of course, no examination of the impacts of an absent predator restored would be complete without the most famous of case studies, the return of the wolves to Yellowstone. Stolzenburg describes how wolves do more than kill and eat elk - there are a lot of elk in Yellowstone, after all, too many for all the wolves to even make a dent in their numbers. Instead, the returning predators, by the very presence, change the behavior of the prey species, forcing them to act in a manner that, while making them less vulnerable to predation, lessens their negative role on the environment. Instead of sitting in one spot and eating every last scrap of greenery, for example, the elk keep on the move constantly so as not to attract the attention of the hunters.
Where the Wild Things Were portrays apex predators not as they are often depicted, as killers lusting after hot blood and fresh meat, but as the gardeners of Eden, who through their actions preserve the diversity and species richness of their environments. They need not be giant or fierce (at least to our eyes) - some are tiny, some are obscure. All, however, have a role to play in maintaining biodiversity. The question is, are we wise enough to allow them to carry out that role?
Our failure to do so may have terrible consequences for nature. As Stolzenburg says, "The biggest and scariest of carnivores may be more dangerous bu their absence."
Where the Wild Things Were: Life, Death, and Ecological Wreckage in a Land of Vanish Predators, at Amazon.com