Erhai Lake in Yunnan shines as China’s success in ecological restoration

People in southwest China's Yunnan have gradually restored the iconic Erhai Lake to pristine ecological condition, with the lake's rejuvenated shores drawing flocks of tourists following years of dedicated anti-pollution efforts.

Located in the province's Dali Bai Autonomous Prefecture, Erhai Lake is one of China's largest freshwater lakes, and sits at some 2,000 meters above sea level and stretches more than 250 square kilometers.

A major tourist draw, the ear-shaped freshwater lake has attracted tens of millions of tourists every year since local tourism began flourishing in the 1990s.

"It's totally worth visiting. It is very clean and bright. I feel so comfortable here," said Deng Debiao, a tourist who was sitting at the lake bank and enjoying the beautiful natural scenery.

In late 1990s, the body of water was plagued by algae and pollution. Large outbreaks of toxic blue-green algae occurred in the lake in 2003 and 2013, turning the picturesque lake in green and with pungent smell.

In 2015, during an inspection tour of Yunnan, Chinese President Xi Jinping, who is also general secretary of the Communist Party of China Central Committee, visited a village near the lake and called on the residents and the local government to protect it.

"In 2017 and 2018, the average total phosphorus concentration across Erhai Lake was 29 micrograms per liter. This year, it's 20 micrograms per liter. While it seems like just a nine-microgram drop, this is a hard-won and remarkable achievement. A decrease in total phosphorus means a clear reduction in algae in the lake," said Wang Xinze, director of Shanghai Jiao Tong University Yunnan Dali Research Institute.

In recent years, Yunnan's local government and ecological management companies have been tirelessly working to intercept pollution at its source, protecting the province's natural treasures.

"Upon the operation of the project, the full collection and treatment of wastewater from all the villages and townships around Erhai Lake can be covered," Li Jianjun, general manager of China Water Environment Group Dali Erhai Branch.

More than 100,000 septic tanks were installed in villages, and thousands of kilometers of pipes were laid, which means that wastewater that once flowed into the lake is now cleaned, and even after treatment, it doesn't reach the lake.

This system's success depends on engineering projects, scientific support, and the cooperation of every household.

"The Dali Bai Autonomous Region proposed four governance measures and one network on Erhai Lake protection. Specifically, the lake should be managed and protected through engineering subjects, according to the laws, in scientific methods, and with joint efforts of all people here. Plus, we have introduced grid-based management system for the lake protection," said Wang.

The restored ecological environment around the lake also brought confidence to many business runners.

"Investing in an upscale guesthouse requires a significant commitment. But Erhai now has been well-managed, and the government gives us dedicated support, which brings us much confidence moving forward," said Fu, a leisure home-stay hotel owner.

Besides engineering projects, scientific methods and joint efforts make by local government and residents, the law-based governance also plays a crucial role in the ecological restoration of Erhai.

"Erhai has its own protection regulations clearly outlining what is prohibited and what is allowed. We always strictly review everything according to these laws and regulations," said Sun Xiao, deputy director of Erhai Administration Bureau.

Erhai Lake in Yunnan shines as China’s success in ecological restoration

Scientists in Peru and Chile are racing to reverse the sharp decline of Humboldt Penguins, a warm-climate species uniquely adapted to the Pacific coast, as climate change and avian influenza threaten its survival.

Peru and Chile are home to the Humboldt penguin, named after the cold water current which flows from Antarctica up the Pacific coast of both countries. It is one of the very few penguin species in the world that lives in a warm climate. Scientists call them a sentinel species -- thermometers of the overall health of the ecosystem.

The penguins nest in Punta San Juan, a small national reserve in southern Peru. They are one species among many marine predators that rest and reproduce here in huge numbers. Biologist Susana Cardenas leads a team that is monitoring and researching these animals and birds. What the researchers have seen in recent years is a dramatic population decline in all species, but particularly penguins, and they are trying to find out why.

"In the last few years, we've seen a decline in the Humboldt penguin population. So, we can go back to 2022 in Punta San Juan, there were about 2,500 Penguins -- that was the size of our colony. And then, well, we had avian influenza that has hit wildlife really hard in Peru and in different places of the world," said Cardenas.

But the impacts didn't stop there for the penguins, which are classed as having vulnerable conservation status, Cardenas explained.

"After that, unfortunately, an El Nino in March of 2023 started and the marine conditions changed and the food availability was not the same. And the penguins, they were getting ready for their breeding season and that's when the marine conditions changed and they did not come back to breed," she said.

In Punta San Juan, penguin numbers dropped from 2,500 to 400 just as Peru's population plummeted from 15,600 to 5,000 all across the birds' range in Peru and Chile, according to Cardenas. That's why continuous data collection is key to maintain the decades of research.

Interns like Sandra Alcantara keep a daily count of the number of nesting penguins and chicks.

"I come here at 6 a.m. to conduct a penguin census. I count all the penguins in a specific age group: adults, juveniles, fledglings, and chicks. Right now, we're in the breeding season, so most of them are adults. So far, I've only seen two juveniles. As the weeks go by, I'll be able to see chicks and then, later on, fledglings," said Alcantara.

The penguins naturally make burrows in the guano, sea bird droppings which build up over decades. Field coordinator Kevin Farfan checks to see if there are any birds in the burrows.

"We are now observing in real time a gradual increase in the number of adult individuals resulting from successful reproduction -- a rise that is slow but steady -- and that gives us great cause for celebration," he said.

These animal populations, while apparently abundant in Punta San Juan, are also highly sensitive to change. Without the tireless dedication of these scientists and volunteers, Peru and the world could lose one of its iconic birds.

Researchers work to reverse population decline of Humboldt penguins