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Species-rich vernal pools, such as these in California, could be one target for greater protection under President Joe Biden’s bid to protect 30% of U.S. lands and waters by 2030.

Anthony Arendt/Alamy Stock Photo

Protect species? Curb warming? Save money? Biden’s big conservation goal means trade-offs

President Joe Biden last week unveiled an ambitious conservation goal, unprecedented for the United States: conserving 30% of the country’s lands and waters by 2030, which would require more than doubling the area of public and private holdings under heightened protections.

Conservation scientists welcomed the so-called 30-by-30 goal, announced in an executive order on climate released 27 January. “The ambition is fantastic,” says ecologist Joshua Tewksbury, interim executive director of the nonprofit Future Earth.

But Biden’s order also raises a thorny practical question: Which swaths of land and sea should be the top targets for enhanced protection or management? The order says the effort should aim for a number of outcomes, including preserving biodiversity, curbing climate change, and even creating jobs and reducing social inequality. But researchers warn that difficult trade-offs lie ahead, because few chunks of territory are likely to provide all of the desired benefits. “The balancing act [will be] the hardest part of this work,” Tewksbury says.

Reaching the 30% goal could require extending protection to vast expanses of land and sea, depending on how officials define “protected.” Only about 12% of U.S. land is already in wilderness areas, wildlife refuges, national parks, and other reserves with strong protection, according to the U.S. Geological Survey. Much is in Alaska; just 7.5% of the lower 48 states is highly protected. (An additional 18% of all U.S. land has weaker protection that allows certain uses, such as logging or mining.) At sea, the country is much closer to the goal: Some 26% of coastal waters is protected to some degree within sanctuaries, national marine monuments, or other entities.

Conservationists have long argued that the current protections are not adequate. Some note that just 11% of species of conservation concern are well-represented on highly protected land in the United States. (Biden’s climate plan from his campaign listed “slowing extinction rates” as a goal, although that phrase doesn’t appear in the executive order.) Increases in protection that benefit species could also provide ecological benefits to people, they add, such as by protecting forested uplands that produce clean water.

Last week, researchers at Boston University and the Nature Conservancy released a discussion paper that maps and compares scenarios for reaching the 30% goal in the coterminous United States (which does not include Hawaii and Alaska). The scenarios examine trade-offs among four goals: minimizing cost, protecting climate-resilient landscapes, protecting species, and curbing carbon emissions.

Making cost the top priority led to expansive new protection in the western plains, where land is cheaper (see map, below). But because most of the added land supports relatively few threatened species, the scheme would fall short on that measure. The least cost scenario also protected relatively little land that absorbs or stores climate warming gases such as carbon dioxide or methane.

Different options

Two possible scenarios for increasing protection of land lead to different locations for conservation, showing the difficulty of optimizing multiple goals.