Declining biodiversity is like a world full of booby traps. A major reason for decline is loss of habitat; humans appropriate land and resources that once supported other life. In addition, the release of toxins from human activity has unknown effects, some of which may only be obvious after lengthy accumulation, appearing years later.
Of course, biologists can now perceive a great deal that was not known in earlier times, stoking alarm about matters of which we were blissfully unaware. But from what is known, we're strumming tunes on the trip wires of a lot of booby traps. Here are just a few that merit a dab of publicity now and then:
- Disappearing bees: Complete loss would severely crimp both the quantity and quality of the human food supply.
- Disappearing frogs: Their role in the human food chain is less obvious, but one is controlling the pest population in wetland areas.
- Fishery collapse: Taking too big a catch is an obvious cause, but made even worse if spawning sites are disrupted so that the population rebuilds slowly -- or never comes back.
Trying to create an image of biodiversity loss in media sound bites is daunting. A few animals are markers of diversity loss. One of the most famous in the United States is the spotted owl in the Pacific Northwest. It is a marker for the health of the underlying ecosystem that supports it, old growth forest, so saving the spotted owl became a symbol for ceasing the logging of the remaining old growth forest.
Out of work loggers naturally resisted this idea, referring to its proponents as "tree huggers." A casual look about in that region suggests that there is no shortage of trees to cut. Large logging organizations have agreed that it's not in their interest to strip out all old growth forest, so they replace the trees they cut. But that is not the case with all small loggers desperate for money. The situation is a mild version of the same condition in Africa or almost anywhere else. People do what they think they must to stay alive -- or to make a pile of money and get to a better place. Side issues on this are still in full controversy.