Mass extinctions are happening. Can they be stopped?

Scientists, conservationists and government representatives will gather this week in Montreal to decide on a plan to stop a stunning loss of plant and animal life around the globe. The United Nations' COP15 — a conference on biological diversity — offers a rare chance for countries to set mutual commitments and milestones for restoring and protecting key lands and waters.

The much-delayed and anticipated conference comes three years after a U.N. report found that more than 1 million species are at risk of extinction within the next few decades. Scientists are calling it the earth's sixth mass extinction — the first caused by humans. The decline has already begun and is affecting every part of the world, including Minnesota where at least 150 species of animals and plants are on the verge of disappearing.

To reverse the trend, nations need to set concrete goals for saving land, funding restoration and protecting species, said Jeannine Cavender-Bares, a professor of ecology, evolution and behavior at the University of Minnesota.

Any commitments need to be clear, precise and measurable. They need to be monitored as they're implemented.

"Scientists are really worried that these targets are getting watered down," she said.

The biodiversity conference has been largely overshadowed by the UN's COP27, a gathering held last month in Egypt to address problems wrought by a changing climate. That conference made little progress on measures to cut greenhouse gas emissions, but led to the creation of a fund that would help especially vulnerable nations.

Governments have debated biodiversity goals for years. In 2020, the UN released a proposed framework that included dozens of milestones. The proposal called for all nations to work together to stop any rise in the extinction rate by 2030. Countries would need to halve the rate that invasive species are spreading and upending new ecosystems. They would also need to ensure that 20% of degraded fresh water lakes and rivers are in some form of restoration within the next eight years. Each country would need to work to keep diverse gene pools in wild and domestic animals. Richer nations would need to contribute up to $700 billion a year to protect lands and waters.

Perhaps the most ambitious goal would be what is known as the 30 by 30 plan — to protect 30% of the earth's land and water in some form of conservation by 2030. The Biden administration has adopted the goal for the United States, although it is still unclear what land the administration considers protected.

By any measure, the state of Minnesota is well short of the goal, which it has not adopted. About 7% of Minnesota's land and water is permanently protected, according to the U.S. Geological Survey. That number rises to 18% if it includes protected areas that allow multiple uses such as logging, mining and off-road vehicle riding.

None of the milestones have yet been agreed upon. Scientists fear that they will be replaced by vague promises.

"If we can have the funding to implement the targets and make very clear definitions for what we mean when we say 'restoration' or 'rehabilitation,' if we do the work to establish those things, we will make a huge difference," Cavender-Bares said.

Natural spaces don't necessarily need to be protected like a national park or wilderness area to provide critical benefits, said Becky Chaplin-Kramer, lead scientist for the University of Minnesota and Stanford University's Natural Capital Project.

She is the lead author of a study published Monday in the journal Nature that found that protecting 30% of the world's land would not only help biodiversity, but help save the vast majority of ways nature helps humans thrive. That includes mitigating floods, protecting water quality, keeping nitrates and sediments out of rivers and drinking water, and supporting economies that rely on timber, fishing or tourism. She'll present the findings Dec. 9 at the conference.

"Too often we think of conservation as being at odds with livelihoods and opportunity," she said. She hopes the findings will help states and communities prioritize saving natural areas or maintaining working lands such as timber forests and grazing ranches in places that provide the most benefit to people.

"We can't just pay attention to the places that are beautiful and remote, which are super important, but we need to remember the places that are closer to home," Chaplin-Kramer said.

Past UN conferences on biodiversity have fallen short in many ways, with nations failing to meet or ignoring goals. But as land continues to degrade and more species are lost, including those that were thriving just 20 years ago, awareness and urgency are growing, said Joanna Benn, a spokeswoman for the Nature Conservancy, an environmental advocacy group.

"People are realizing we need to see more movement than we have," Benn said. "Everyone intuitively knows that things aren't right. We can all see it."