Scientists at Defenders of Wildlife and Tufts University have discovered that habitat loss in the U.S. was double on private lands compared to federally protected lands. The study, published today in Frontiers in Ecology and the Environment, shows that federal land protection and listing under the U.S. Endangered Species Act are effective tools for slowing habitat loss.
“At a time when our planet faces a looming extinction crisis, we need every tool available to protect species and their habitats,” said Jacob Malcom, one of the study’s co-authors and the director of Defenders of Wildlife’s Center for Conservation Innovation. “This research illuminates the critical importance of America’s federal lands system and the urgent need for better protection on private land as well. Biodiversity and the services it provides to society can be conserved through concerted effort and transformative change, and protecting habitats must be a part of the solution.”
Habitat loss and altered landscapes are the primary cause of biodiversity loss, directly reducing population size and reproductive rates for many common and endangered species. However, regulations for habitat protection are different for private lands, where reporting of environmental impacts is not required as it is on federal lands. For decades, scientists have worked to identify the most effective ways to prevent future habitat loss, but most studies have had a limited geographic scope or focused on one or a handful of species at a time.
To understand the habitat loss, the researchers used 30 years of satellite images. The habitats examined for this study feature species that have ranges, including both federal and private lands and that cover 49% of the U.S. from coast to coast -- including all major ecosystems in the continental U.S.
“We know from research conducted by other scientists that development surrounding protected areas can reduce the effectiveness of those protections for animals,” said Adam Eichenwald, lead author of the study and biology graduate student at Tufts. “Not only that, but climate change can force species to leave these spaces, which we worry may eventually result in areas designed to protect species that have moved away.”
The researchers used satellite imagery data collected between 1986 and 2018 to map out the range of 24 species ranges. They tracked habitat change in those ranges over time using the LandTrendr algorithm on the Google Earth Engine platform. The data revealed that imperiled species lost the least habitat (3.6%) on federally protected lands and lost the most habitat (8.6%) on private lands lacking conservation easements. State lands and lands protected by non-governmental organizations had losses of species habitat equivalent to one another, and less than loss in private lands protected by conservation easements.
“By zooming out to the national level, the study provided us with a unique opportunity to examine whether certain regulations and jurisdictions were more effective in protecting habitats of endangered species,” said Michael Evans, senior data scientist at the Center for Conservation Innovation at Defenders of Wildlife and co-author of the study. “We now have a much clearer picture of just how tied habitat preservation is to federal protection, and the unique role the Endangered Species Act plays.”