In July, about 20 7- and 8-year-olds will gather at a summer camp in the Hoopa Valley Indian Reservation in Northern California. They will sing songs, put on puppet shows and play games.

And there will be one special rule: No English.

This five-day summer camp is held almost entirely in Hupa, the native language of the roughly 4,000-member Hoopa Valley Tribe that mostly lives in that part of the state.

For decades, native speakers of Hupa, also known as na:tinixwe mixine:whe, have dwindled. Only about 20 people are fluent enough today to teach the language and pass it on, tribal members estimate. The camp is a bet that immersion at a young age can help change that.

“That’s always the goal,” said Sara Chase, a member of the tribe who organized the camp with the Hoopa Tribal Education Association. “How do you create new speakers?”

As the number of languages spoken globally is in steep decline, it’s a goal shared by an increasing number of indigenous communities seeking to maintain a core part of their culture, inextricably tied to their history and way of life.

“We are facing a really interesting chapter of human history where people are going against the tide to keep their language alive or bring back languages that are dormant,” said Gabriela Pérez Báez, professor of linguistics at the University of Oregon.

Some experts predict that half of the roughly 7,000 languages in existence today will lose all fluent speakers by the end of this century.

In surveys of about 245 language revitalization programs that Baez, director of the university’s Language Revitalization Lab, conducted in 2016 and 2017, more than half began after the year 2000. About 30% started after 2010.

“It just goes through the roof,” she said.

The story of the Hoopa Valley Tribe stretches back thousands of years, to when the tribe first populated the region that would become Northern California, Chase said.

The valley itself is where the Trinity River cuts through the mountains. Tribes in the area used redwood trees to make homes and canoes.

The discovery of gold in the mid-1850s brought white people — and violent conflict — to the area. In 1893, the Bureau of Indian Affairs created the Hoopa Valley Indian School, where, as at other such boarding schools around the country, white teachers burned traditional clothing, gave children Anglo names and forbade them to speak the language of their parents.

“Some would say that whenever they try and speak the language, they could taste the soap in their mouths,” said Daniel Kaufman, director of the Endangered Language Alliance, a nonprofit group in New York.

Schools did eventually begin to teach na:tinixwe mixine:whe, but not enough to create new fluent speakers, Chase said.

“Time is finite; that is always scary and always something that I think is in the back of our minds,” said Erika Tracy, executive director of the Hoopa Tribal Education Association, which oversees tribal educational programs. “I just feel that urgency, to know that we need to learn, and we need to learn fast, and we need to teach fast to sustain our language and everything that comes with that.”

Chase’s immersion camp began in summer 2017. She had graduated from Columbia University in 2014, where she majored in Native American studies and linguistics, after growing up on the reservation. She is enrolled as a Hoopa Valley Tribe citizen.

There are precedents showing that a small effort like Chase’s can have a large impact. Two of the most prominent language revitalization efforts, of Maori in New Zealand and of Hawaiian, started in a similar fashion.

By the 1980s, the number of fluent native speakers of the Hawaiian language had fallen to about 1,500. Professors at the University of Hawaii at Hilo set up a preschool where older Hawaiian speakers taught the language. Slowly, adding a new grade each year, they succeeded in creating a preschool-to-high-school system in which Hawaiian is the primary language of instruction.

In New Zealand, activism by community groups led to the kohanga reo movement. Beginning in 1982, it immersed Maori preschoolers in the Maori language, among other efforts to recover the language. Maori became the official language of New Zealand in 1987.

Today, indigenous people are increasingly embracing the language. The New Zealand government said it wants more than 20% of the country’s population to speak basic Maori by 2040 and has pledged to provide Maori lessons in all schools by 2025.

One of the goals of such revitalization efforts is to restore confidence. Baez said “the loss of the language is a very tangible evidence of the oppression that a people might have suffered” and that it “signals a significant defeat and vulnerability.”

For Chase, it’s about a resurgence of a way of life damaged by colonialism.

“It really is a whole other way of looking at the world, of feeling,” she said. “There’s just so much power in the language.”