The city of Marquette in Michigan is closing a section of a road to vehicular traffic every night to protect migrating salamanders (蝾螈). From 8 p. m. to 8 a. m. daily until April 15 or until the migration is completed, a section of Peter White Drive in Presque Isle Park will be closed, the city announced.

“Protecting the blue-spotted salamanders’ migration is vital, as they are an indicator species, informing us about the health of our environment,” said Kathleen Henry, Superior Watershed Partnership (SWP) special projects coordinator (协调员) and education specialist. The salamanders spend the cold winter under-ground. Then every spring, they make their way to the water where they lay eggs.

It was in 2018 that Eli Bieri, a former Northern Michigan University student, noticed vehicles were killing hundreds of these migrating salamanders. “We would see thousands and thousands of salamanders crossing the street in just one night,” Bieri told the Detroit Free Press. “It was really amazing — until we see cars pass by and squish salamanders. That really troubled me — it kept me awake at night.” He enlisted the help of the SWP, who reached out to Marquette city officials. Last spring they got the relevant stretch of road within the park temporary closed to evening and overnight vehicular traffic.

In 2019, before the closure, they found 429 salamander carcasses (尸体) in the road. Last year, they counted only 3 carcasses. With that success demonstrated, city officials are doing the same this year. “The goal is to apply our science to wildlife management,” Bieri said. “To be able to see in-person the science applied to successful management practices was very satisfying.”

It was late August when I got a call from a grandmother. She lives in Seeley Lake, Montana, and she has heard we have air purifiers (净化器) with high-efficiency particulate air (HEPA) air-cleaners that can help with smoke. She needs one for the baby’s room. I explained we didn’t have any and told her how to purchase one.

She coughed and went silent with disappointment before asking how much they cost. Almost every person I talk to in Seeley Lake has this cough. “The family doesn’t have much money,” she said, but she promised to order a filter for the child. Small filters—ones that can clean a bedroom of up to 75 square feet—cost about $70 each.

The next day, the wildfire that had been burning for weeks in the Lolo National Forest, northeast of town, moved closer to the woman’s neighborhood, and the county sheriff’s office evacuated (疏散) the area. I wondered whether the air-cleaner would be there when the family returned home. I knew the smoke would be.

As an air-quality specialist with the Missoula City-County Health Department in Montana, my job is to understand air pollution, control it as much as possible, and help people protect themselves from its effects. I focus on smoke management: issuing permits for outdoor burns and updating residents about what to expect from the smoke when wildfires send it our way.

Never had we seen so many wildfires so close to home for so many weeks. There are six classes on the Environmental Protection Agency’s Air Quality Index (指数): good, moderate, unhealthy for sensitive groups, unhealthy, very unhealthy, and dangerous. Seeley Lake’s air reached dangerous class in 18 days last summer.

Last year was troubled by wildfires around the country. The fires that struck Northern California alone killed 44 people and caused more than $9 billion in damage. But this isn’t just a recent problem, nor is it limited to the West. Wildfires hit 49 states in 2017, including a swath from Florida to Virginia. More than 9 million acres burned nationwide, compared with the yearly average of 6.5 million acres.

There are many ecosystems that are truly suffering from degradation (退化). The solution is that they can be restored by re-introducing several animal species. The United Nations funded a study that shows that if you introduce 20 specific large mammals you can successfully restore a lot of the planet.

Some roles that species play in the environment are critical, so the loss of any of these can harm the world. So that means that on the other hand, re-introducing a species can produce positive results. When a few wolves were re-introduced to Yellowstone Park is one of the most cited examples. There is no doubt that the re-introduced wolves did restore the ecosystem.

Dr. Carly, a scientist, along with her team, was able to identify 13 herbivores (食草动物) and 7 predators (食肉动物) that if re-introduced, could help restore a lot of what we’ve destroyed in nature. One species can benefit its environment in a dramatic way, helping create more soil insects and worms.

The team compared environments from 500 years ago to conditions of modern environments to know how travel and the industrial revolution have influenced the planet. And at last they figured out that only 16% of the world still has undamaged wild mammal communities and just 6% looks similar to what it looked like pre-1500.

They suggested that a 54% expansion in territory home to undamaged mammal communities can easily be accomplished, especially in South America and northern areas of Africa. In Europe, re-introducing beaver, bison, wolf, and reindeer could really make a dramatic impact. However, just wolves and wild horses could make a difference to Asia.

“Our recommendations may not be suitable everywhere in the world — local assessments will judge if hunting pressures or the lack of adequate preys mean other issues need addressing before reintroducing them. However, our findings show there are huge areas of the world that could be suitable for large mammal restoration if other factors are managed,” said Dr. Carly.