More than 2,400 languages around the world are in danger of extinction, according to Unesco, and the US is second only to India in having the highest number of endangered languages.
Sikumi is the first film to be written entirely in Alaska's Inupiaq language
The US has already lost more than a third of the indigenous languages that existed before European colonisation, and the remaining 192 are classed by Unesco as ranging between "unsafe" and "extinct".
As recently as 2008, the Alaskan tongue Eyak became officially extinct with the death of Marie Smith Jones, the last native speaker.
"We need more funding and more effort to return these languages to everyday use," says Fred Nahwooksy, of the National Museum of the American Indian.
"We are making progress but money needs to be spent on revitalising languages, not just documenting them. A lot of tribal communities say that is a defeatist attitude, as if these languages are expected to become extinct."
Some 40 languages, mainly in California and Oklahoma, where thousands of Indians were forced to relocate as part of the notorious 19th Century Trail of Tears, have fewer than 10 native speakers.
"Part of the issue is that tribal groups themselves don't always believe their languages are endangered until they're down to the last handful of speakers. But progress is being made through immersion schools, because if you teach children when they're young it will stay with them as adults and that's the future," says Mr Nahwooksy, a Comanche.
Such schools have become a model in Hawaii.
But the islanders' indigenous language is still classed by Unesco as critically endangered because only 1,000 people speak it.
The decline in American Indian languages has historical roots: in the mid-19th Century, the US government adopted a policy of Americanising Indian children by removing them from their homes and culture.
Language is the distillation of hundreds, if not thousands of years of experience of a collective... So when the language disappears you're really throwing away that whole library of knowledge
Within a few generations most had forgotten their native tongues.
But even so-called "dead" languages can be brought back to life.
The Wampanoag Indians of Massachusetts were the first to greet the pilgrims of the Mayflower - but until recently their language had not been spoken for a century.
In 1993, tribeswoman Jessie Little Doe Baird began researching and collecting word stems.
Now her daughter is the first native speaker in six generations and other children are learning.
Modern challenges to language survival remain.
"We said back in the 80s that technology was killing our language and now every home has a television," says Inee Yang Slaughter, director of the Indigenous Language Institute in Santa Fe, New Mexico.
"While on the one hand that's a welcome sign of technology, it's also brought English into homes and pushed out traditional story-telling and family time together. The language has dissipated - and that's just a small example of the sorts of challenges we face."
There is a growing movement in the US to try to revitalise indigenous languages, but regaining the trust of community elders who were often punished for speaking their own language can be a problem.
Many now have to be persuaded to pass it on to a younger generation.
"In many situations it's having to be taught as a second language because there isn't an environment where the language is used every day," says Ms Slaughter.
"Communities have had to adopt programmes that are classroom-based and there is a lack of teachers and materials."
Ms Slaughter says she is encouraged that young people are showing a greater interest in learning their native tongues.
But interest alone may not be enough as the search for jobs forces people to leave the only communities where such languages are spoken.
People seem to understand how important it is to preserve tangible heritage like the Seven Wonders of the World. Well, language may not be visible, but it's just as rich and just as important to humanity
Inee Yang Slaughter
"I don't live near home so I don't have the language incorporated into my everyday life," says Rachel Nez, a native Navajo speaker from Arizona.
"To have that I would have to move back to the reservation and be there all the time - but if I did that I wouldn't be able to do what I can do here."
With 120,000 speakers, Navajo is considered "unsafe" by Unesco rather than actively endangered.
But its survival is still dependent on bringing up a new generation of speakers who, like Rachel, see language as an integral part of their cultural identity.
"A lot of history, culture and ceremony is held within the language. Sometimes I'll come across Navajo people who don't speak it, and it's really hard for me to accept that they're Navajo because they don't share that thing and those experiences with me," she says.
"Language is the distillation of hundreds, if not thousands of years of experience of a collective. It's considered sacred knowledge. So when the language disappears you're really throwing away that whole library of knowledge."
While the American media is often blamed for undermining other languages and cultures, the same technology might become the native languages' best chance for survival.
Native American filmmaking is a growing industry, providing a unique voice for communities that are often wary of being photographed or recorded in any form.
In New Mexico, Tewa children are allowed to make audio recordings of their personal stories and experiences as part of oral history projects, but they must seek permission from the elders before the material can be shown outside the community.
"Some cultures have been extremely invaded," says Elizabeth Weatherford, head of the Film and Video Center at the National Museum of the American Indian in New York.
"They have had lots taken but little given back."
She is also director of the Native American Film and Video Festival which celebrates its 30th anniversary this year.
Dozens of native language films are being shown, including the first to be written entirely in Alaska's Inupiaq language.
Sikumi/On the Ice, by Andrew Okpeaha Maclean, premiered at the Sundance Film Festival and was short listed for an Academy Award.
"Anything that can activate young people who have been saturated by the American media is really important," says Ms Weatherford.
"Film making can make them empowered by the use of language in their own world. It's the transmission of language through culture and there's an effortlessness to it."
Some academics have argued that the demise of a language is simply part of social development and evolution. But Ms Slaughter disagrees.
"People seem to understand how important it is to preserve tangible heritage like the Seven Wonders of the World. Well, language may not be visible, but it's just as rich and just as important to humanity."
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.