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New Releases, University of Michigan Press

Guest blogger Dennis Wild is the author of the newly published The Double-Crested Cormorant: Symbol of Ecological Conflict, which tells how, after cormorant populations rebounded from near-extinction driven by DDT contamination, these amazing birds were persecuted throughout their entire range  because of their perceived threat to American fishing interests.

Today’s double-crested cormorants face the challenge of being referred to as “overabundant.” Their numbers had been so low for so long that more than one human generation grew up never seeing large gatherings of cormorants, either at their breeding grounds on the Great Lakes and other northern areas or favorite wintering quarters in the Gulf States and Florida. But when cormorant numbers rebounded after DDT was finally banned in 1972, fishermen, politicians, and even bird watchers were astonished at their growing numbers. Some local populations doubled in three years. Even though cormorant populations were probably still below their historic highs, people involved in fish and fishing soon saw the bird’s large flocks as “out of control.” In other words, the birds were eating too many fish. So they, meaning catfish farmers, fishermen, and government technicians, shot them – by the tens of thousands. The remains of the birds were usually composted onsite or elsewhere since the meat is inedible—a cruel, terrible waste of food chain energy and biomass.

Now, as noted in a recent New York Times article, it is the Sandhill Crane, Grus canadensis, that is coming under the gun as an “out-of-control” species. After decades of conservation efforts in many locations to protect thinning numbers of rare sandhill cranes, which became threatened due to overhunting in the 1930s, conventional wisdom now turns to lethal measures to control a perceived “overabundance.” The evolutionary line of cranes goes back about 10 million years, with distinct sandhill crane ancestors appearing about 2.5 million years ago; like cormorants, there are several subspecies of sandhills, but unlike today’s cormorants, some are rare or endangered.

Sandhill cranes are not big fish eaters, so they’re not in competition with fishermen or fish farmers. The cranes are basically opportunistic herbivores, living off whatever plants or seeds are available at the time; they can manage to find food in drier upland areas as well as shallow wetlands. Sandhill cranes dine on wild berries, seeds of many kinds, and when the possibility presents itself, small mammals, reptiles, amphibians, and invertebrates such as snails and insects. What actually brings them into conflict with man, particularly farmers, is their decided taste for cultivated foods. Sandhills frequently target recently planted corn and wheat fields, much like cormorants raid the densely stocked catfish ponds in the South in search of an easy meal.

To protect their fields, farmers in Wisconsin are requesting the creation of legal hunting seasons for sandhill cranes. More than a dozen states, with more in the offing, have established seasons, bag limits and takes for this once rare bird. Unlike cormorants, however, the flesh of sandhill cranes is edible and is reported by hunters to taste much like pork chops, so the birds are not merely killed and composted, but are also consumed.

Regardless of whether the carcasses are destined for the compost or the dinner table, it seems, at best, inefficient to spend decades reviving a rare, threatened species only to turn around and put it in hunters’ sights. What is really ignored here is the question of why the birds feed at agricultural sites rather than at open upland ranges or food-rich shallow wetlands. The one-word answer is habitat. Every day more and more open land is taken out of the natural food chain and converted from prairie or open range or upland habitat or wetland to real estate – development or reclamation projects – restricting the bird’s range, driving it into direct conflict with humans.

In science fiction literature and physics thought experiments it’s common to postulate what happens when human subjects are locked in suspended animation and time goes on without them. When they awaken the world has changed and there is no place for them in the future. The return of nearly-extinct species sometimes falls into this type of scenario. There often comes a point when threatened wildlife species regain some of their original stature, attempt to re-colonize former territories and expand into new ones, but during the decades of their absence people forgot what they were, how plentiful their numbers had been, and their place in the ecosystem. In that future, the returning wildlife has lost its claim to respectable habitat and moves into territory appropriated by humans in its absence, setting the stage once again for lethal control measures of “overabundant” species, even the ones that taste like pork.

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