A new study supports an approach to conservation that focuses on ecoregions—geographically unique regions, such as deserts and rainforests, that contain distinct communities of plants and animals.

Scientists have long debated how well ecoregion borders separate species communities. If the borders are strong, protecting an ecoregion, like a rainforest, would effectively protect all of the species within. If not, each species would need to be managed separately—a much more uncertain undertaking, especially when we don’t even know some species are there.

For example, no one had reported seeing the presumed-extinct Wondiwoi tree kangaroo—an animal that is a cross between a bear and a monkey—since before the Great Depression. Then, this past summer, an amateur biologist stumbled upon the tree kangaroo while trekking through Papua New Guinea. The revelation underscored how little we still know about the natural world—a major obstacle to conservation.

The new study, which appears in Nature Ecology & Evolution, provides compelling evidence that ecoregions do meaningfully divide plant and animal communities. This opens a path to new conservation approaches that more affordably and effectively protect little-known species—such as the tree kangaroo—and valuable natural services such as disease control and water filtration.

“Environmental conservation is limited by a lack of funding and other resources,” says lead author Jeffrey Smith, a graduate student in biology at Stanford University. “Ecoregions give us a way to effectively allocate that limited funding.”

CONSERVATION AND RESTORATION

Robust, scientifically based conservation depends on in-depth information about species, their habitats, and their population numbers—a level of detail absent for the overwhelming majority of species and places around the world.

Looking for a way to bridge the gap, researchers did a deep dive into plant and animal biodiversity data from sources such as the US Forest Service and the Global Biodiversity Information Facility, a clearinghouse for data from citizen scientists, museums, and researchers.

From that, they unearthed support for thinking about all species—even highly mobile animals—as being clustered together in ecoregions around the globe. These results go far beyond previous work, which primarily characterized ecoregions by plant communities alone.

“These are crucially important findings,” says coauthor Gretchen Daily, a professor of environmental science. “They illuminate where and how to invest in conservation and restoration for people and nature.”

HOLISTIC APPROACH

The future of Earth’s life-support systems hinges on vast yet little studied regions of the planet. Establishing that ecoregions meaningfully divide different types of communities allows scientists and decision-makers to think more critically about conservation plans for these realms.

This holistic approach to protecting biodiversity ensures we can better safeguard natural services, such as crop pollination and pest control, that diverse ecosystems of plants, insects, fungi, and small vertebrates make possible.

Ecoregions are one of many factors that should be considered when developing a cohesive conservation strategy, the authors argue. It’s an approach already in play at some major global conservation organizations, such as the Nature Conservancy and the World Wildlife Fund, as well as federal agencies, such as the US Environmental Protection Agency.

Additional coauthors are from Stanford, ETH Zurich, and the University of Toronto. The National Science Foundation, the Stanford Department of Biology, and the Ward Wilson Woods Jr. Environmental Studies Fund funded the work.