Top Predators Are Good for People?

When Defenders pushed for bringing gray wolves back to the Northern Rockies in the mid-1990s, we knew that we were supporting something even bigger: the restoration of whole ecosystems. Top predators, like wolves, bring balance to their habitats. Without them, that delicate balance falls out of whack and all animals tend to suffer. But just how important are predators to human life on Earth?

A new report, “Trophic Downgrading of Planet Earth,” published in Science last Friday suggests they’re far more crucial than you might have previously thought. It confirms that human-caused decline of large predators is resulting in widespread damage to the world’s land, freshwater and marine ecosystems: “[t]he loss of apex consumers is arguably humankind’s most pervasive influence on the natural world, […] with far-reaching effects on processes as diverse as the dynamics of disease; fire; carbon sequestration; invasive species; and biogeochemical exchanges among Earth’s soil, water, and atmosphere.”

In our backyard, hungry deer browse over suburban gardens — owing to the decline of wolves and their other predators – and all too often wander out into the streets with deadly results. Vehicle collisions with deer claim more human lives each year than any top predator in the United States.

Defenders took a leading role in enabling these findings by providing important financial contributions for a workshop at White Oak Plantation that led to this study. Based on a review conducted by an international team of 24 scientists, this seminal report finds that — in addition to damage caused by the overabundance of prey — the decline of predators contributes to the spread of disease, wildfires and invasive species, all of which have significant impacts on the quality of human life.

For example, the decline of vultures in India led to increased health risks from rabies and anthrax. In sub-Saharan Africa, lion and leopard losses have led to an overabundance of disease-carrying olive baboons, which are increasingly coming into contact with humans and eating crops. In our backyard, hungry deer browse over suburban gardens — owing to the decline of wolves and their other predators – and all too often wander out into the streets with deadly results. Vehicle collisions with deer claim more human lives each year than any top predator in the United States.

What Defenders is Doing

This review’s findings suggest cascading effects on ecosystems are also exacerbated by land use practices, climate change, habitat loss and pollution.  Defenders is dedicated to protecting and restoring large predators, both through our support for ground-breaking research and our accomplishments in the field. Our work to protect sea otters and sharks, for example, also highlights the critical importance that these species have to their ecosystems. Without these apex predators, the habitat changes dramatically. It has been shown when sea otter populations have declined dramatically, we are left with a near-shore habitat devoid of plant and animal life as well as the loss of our great kelp forests. Similarly, with the dramatic decline in shark populations, reef systems are changed greatly with “an ecosystem dominated by small fishes and overrun by algae.”

This report comes at a time when endangered species are in dire need of defense, as debate rages in Congress over the future of the Endangered Species Act. The Interior Appropriations bill would strike a blow to the very heart of the ESA, allowing wildlife protection to be weakened, but never strengthened.

Take Action: Stop the all-out assault on the environment.

Extinctions, especially in light of this Science review, can have unanticipated and devastating consequences. It’s high time that Congress reassesses its priorities and opposes this piece of legislation, before the tide of extinction is irreversible and backfires on all of us.  In the meantime, Defenders will keep sticking up for endangered species.