Andrew Johnson

A biodiversity crisis

Human activities are causing a biodiversity crisis that threatens the natural world. Habitat destruction, pollution, climate change, the spread of invasive species and overexploitation of wildlife have pushed countless species to the brink. These threats, like a warming planet and widespread wildlife extinction, not only put individual species and places at risk, but also threaten the entire web of life.

Why biodiversity is important

Because nearly every species on Earth relies on the presence and health of other species for survival, we must understand and support these connections. Grizzly bears need butterflies. Orcas need salmon. Black-footed ferrets need prairie dogs. Coral reefs need sharks. And all species—including people—need clear air, healthy water and a sustainable climate. In short, when we save species from extinction, we help preserve biodiversity. And preserving biodiversity helps save the planet.

Biodiversity collage

Sea otters: a keystone species

Take sea otters. Sea otters function as a keystone species, which means that their presence produces an outsized influence on the productivity and diversity of their environment compared to other species. As top predators, sea otters maintain the balance of nearshore ecosystems, such as kelp forests, embayments and estuaries. When fur traders hunted sea otters to near extinction in the 18th and 19th centuries, kelp habitats became barren and less biodiverse. Freed from predator control, sea urchins and other sea otter prey species overpopulated the seafloor and wreaked havoc on the large kelps that provide cover and food for countless other marine animals and plants.

With federal protection, remnant populations of sea otters re-established themselves throughout the 20th century in areas of their historical range. Scientists now understand the importance of kelp and seagrass beds for sequestering carbon dioxide, a prevalent greenhouse gas, and supporting biodiversity in coastal waters. If keystones like sea otters disappear forever, we might never regain the valuable services afforded by kelp forests and other biodiverse ecosystems.

Sea otter

Thankfully, more people today seem to grasp how important keystone creatures are in sustaining biodiversity. In April alone, generous California taxpayers donated more than $110,000 to the state’s sea otter research and recovery fund. And, this September, Defenders will be celebrating the 20th anniversary of Sea Otter Awareness Week, a week dedicated to inspiring a deeper awareness of these unique marine mammals, their ecological importance and the many challenges they face. The salvation of the sea otter is just one example of what can happen when people come together to save wildlife and biodiversity.

Sea Otter floating
Joshua Asel

Scientists, environmental experts and politicians have sounded the alarm about the biodiversity crisis, which threatens the extinction of nearly a million species in the coming decades.

Defenders of Wildlife work on biodiversity

To address these dire warnings, Defenders of Wildlife is calling for the establishment of a National Biodiversity Strategy to guide all 50 states, governmental agencies, Tribes and private stakeholders in protecting our nation’s biodiversity. As the only species that can choose to save Earth’s biodiversity, we have a responsibility to act.

International Day for Biological Diversity is May 22. Will you heed the urgent call for action? Take the pledge to save biodiversity today!


Andrew Johnson

Andrew Johnson

California Representative
As California Representative, Andy's work focuses on sea otter issues in California, Oregon, Washington, British Columbia and Alaska, and he covers threats to California’s coastal ecosystems and wildlife, such as plastics and other ocean pollution, fisheries, energy development, human disturbance and climate change.


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