Biological diversity is what makes the world unique. As the sum of all living organisms, biodiversity is key to the continuation of our existence and function of life of the planet.
A study published July 10, by the Proceedings of the National Academy of Sciences of the United States of America, takes a look at the state of biodiversity and draws the alarming conclusion that we are in the midst of a “sixth mass extinction.”
Authored by Gerado Ceballos, Paul Ehrlich, and Rodolfo Dirzo, the study warns that “the strong focus on species extinctions, a critical aspect of the contemporary pulse of biological extinction, leads to a common misimpression that Earth’s biota is not immediately threatened, just slowly entering an episode of major biodiversity loss.” It is extraordinarily upsetting, but what makes this paper so nuanced is that it takes a critical look at local populations, not only the worldwide populations we so often point to when referencing extinction.
The team analyzed data for 27,600 species of land-based vertebrates, and found that a third of these are in decline. It is important to note that this does not necessarily mean that these declining species are endangered, but Ceballos states that this can provide a false sense of security. The group also analyzed historical data for 177 mammals, and each of those species have lost 30 percent of their historical range and almost half of those species have lost more than 80 percent since 1900.
Ed Yong, writing about the paper in The Atlantic, puts it eloquently: “If a species is completely wiped out, that’s an important and irreversible loss. But that flip from present to absent, extant to extinct, is just the endpoint of a long period of loss. Before a species disappears entirely, it first disappears locally. And each of those local extinctions—or extirpations—also matter.”
Lions, for example, once roamed from Africa to southern Europe and northern India. Now they are located in disconnected pockets, with population numbers falling by 43 percent in the last 20 years.
Giraffe populations have plummeted by 40 percent as well. African elephant populations have fallen by 30 percent and forest elephant populations have declined by more than 80 percent.
“If jaguars become extinct in Mexico, it doesn’t matter if there are still jaguars in Brazil for the role that jaguars play in Mexican ecosystems,” Ceballos said to The Atlantic. “We might able to keep California condors alive forever, but if there are just 10 or 12 individuals, they won’t be able to survive without human intervention. We’re missing the point when we focus just on species extinction.”
International Union for Conservation of Nature (IUCN) data show that habitat loss is the main culprit in this case, followed by hunting/collecting and introduction of alien/invasive species. As stated in the paper, “The massive loss of populations is already damaging the services ecosystems provide to civilization. When considering this frightening assault on the foundations of human civilization, one must never forget that Earth’s capacity to support life, including human life, has been shaped by life itself.”
Based off of this paper and our own experiences, there is no denying that the sixth extinction is here. As noted in the study, population extinction is a prelude to species extinctions. As noted by the University of Maine’s Jacquelyn Gill in The Atlantic, “What's really powerful about [Ceballos’s new] study is that it focuses not on the losses, but on the early warning signals. Population declines are a common precursor to extinction, and it's a process we can actually do something about.”
At the same time, at IFAW we have long believed that we have passed the tipping point and that traditional conservation measures are simply not enough. When you see populations that are under such enormous stress you cannot come to any other conclusion than individuals in those populations do matter. That is why we rescue animals, that’s why rehabilitate animals, and that’s why we provide safe and secure spaces for them to live. And that is the future of conservation.
As an organization we have worked to return Russian Amur tigers to their native habitat. With fewer than 500 of these big cats left in the wild, IFAW has rehabbed six orphaned cubs into the wild. In India, we are actively working to rescue and release rhinos to repopulate Manas National Park. Similarly, fewer than 50,000 Asian elephants remain in the wild. We have raised and released 20 calves that have successfully integrated into wild herds.
Conservation decisions should be guided by ecological and biological sustainability. As human population and development expands, the world’s wild spaces are disappearing, which in turn has a direct correlation to the biological diversity of an area. We need animals, as they are important to people and the planet.
If we want a world where biodiversity is preserved, we must preserve critical habitat for wildlife as human population develops as well.
As summed up in the report, Earth’s capacity to support life is shaped by life itself.