Seeing the headline “South Africa allows killing of elephants” by the Associated Press had me outraged; however, I was even angrier after finding out that humans have so disrupted our planet that this killing is now needed.
The South African policy entails systematically killing a booming elephant population to deal with problems it has caused for the ecosystem. This is only one of many examples that point to an ever-increasing problem facing us today: If policy toward ecosystems and animals does not change, we could face one of the largest mass extinctions in human history.
Perhaps the most concerning part of this story is that human effects on the African ecosystem have made this policy a necessary evil, since without population control the elephants in the area would destroy large amounts of land.
“Elephants historically would move large distances, and under those conditions natural pressures would be more likely to regulate population size,” said ecology and environmental biology professor Tom Smith, acting director of the UCLA Institute of the Environment. “But now with (reserves) of limited size, you need to control populations so that populations don’t overstrip their food supply.”
To contrast this example, park officials at Yellowstone National Park have pursued a policy of slaughtering hundreds of bison to prevent the spread of the brucellosis disease from bison to cattle in the area. The problem is that there is no proof this disease can spread from bison to cattle.
These examples illustrate the problems habitat loss has created for these animals and their ecosystems. Indeed, Smith said part of the problem with the case of the elephants in South Africa was that the loss of habitat has had negative effects on the elephant populations in the area, which need large amounts of land to survive. Also, in the case of the bison, the limited amount of land available has caused the habitat of bison to overlap with that of the area’s cattle.
Smith and Louis Barnatchez of Laval University in Canada wrote a piece titled “Evolutionary Change in Human-altered Environments,” as a preface to a summit on this issue held at UCLA last year. In the paper, they wrote that “two-thirds of the world’s terrestrial land area is now devoted directly to supporting human populations,” and they went on to write that “human-induced evolutionary changes” have essentially affected every part of the world.
However, habitat loss is not the only problem facing the world’s ecosystem. The current climate change induced by carbon emissions from human activity around the world has affected ecosystems in drastic ways. For instance, carbon emissions have affected the snowfall and in turn life in the mountains of California.
“Some of the mountain species have been observed moving up mountains because vegetation and snowfall have changed,” said geography professor Hartmut Walter. “The question is: What happens to the species that live in the area they are moving into?”
Furthermore, if current carbon emissions are not reduced within the near future, we could see a great loss of animal and plant life in our lifetime.
“Up to 30 percent of plant and animal species are at risk of extinction if the average rise in global temperature exceeds 1.5 degrees Celsius,” Smith said. “We are already about at a rise of 0.8 degrees. If we see a doubling, which is predicted, we will see mass extinctions.”
The question then becomes: What can be done to avoid such a mass extinction? Georgina Mace and Andy Purvis wrote a paper titled “Evolutionary Biology and Practical Conservation: Bridging a Widening Gap,” for the summit that was hosted at UCLA last year. In the paper, Mace and Purvis outlined possible methods to address current conservation issues, such as better relationships between scientists and policy-makers, new approaches for conservation, including better ways to allocate resources, and more incentives for scientists to work on conservation policy.
Also, there are a number of policies that could be enacted here in the U.S. alone, such as the Climate Change Adoption Act, the Global Change Research Improvement Act and the Federal Ocean Acidification Research and Monitoring Act, all of which Congress has yet to pass.
As a planet we are at a point where policies must be changed or enacted to preserve the diversity of life on Earth. Failure to do so would not be a result of an inability to understand the problems we face, but rather a result of carelessness on our part as the keepers of our world.
E-mail Margolis at mmargolis@media.ucla.edu if you too want to save the diversity of life on Earth. Send general comments to viewpoint@media.ucla.edu.