In the murky waters of climate change, native fishers are among the most vulnerable

‘The water temperature is getting warmer, and I don’t know if that’s good.’

A treaty signed in 1836 grants members of the Ottawa and Chippewa tribe rights to fish in the waters of Lake Michigan. After nearly 200 years, the treaty is still vital to small-scale native fishers such as Cindi and Ed John, who catch, smoke and sell fish locally. But the interlocked threats of climate change, pollution and invasive species have left them with just a quarter of their former yields. And the problem seems to be getting worse each year – fish once found at a depth of 50 to 60 feet have gone deeper, to 80 to 90 feet below the surface, in search of cooler waters. The US director Jason B Kohl’s short documentary 80 to 90 ft brings a gently wrenching resonance to Cindi and Ed’s reflections on the uncertain future of their culture, lifestyle and business.

Far from sluggish: the remarkable sea creature that weaponises its dinner

Nudibranchs, also commonly known as sea slugs, are a group of snail-like sea invertebrates. Despite appearing more or less defenceless, nudibranchs broadcast their whereabouts with their flamboyant, brightly coloured bodies. From an evolutionary standpoint, it might seem like a curious move, but their luminous skin actually serves as a warning to would-be predators to let them know they’d make for a dangerous meal. While some nudibranchs accumulate toxins and other defensive chemicals in their bodies, others – like the star of this film – have an even craftier method of warding off enemies. This remarkable short from the science and nature documentary series Deep Look details the clever way that some nudibranchs protect themselves by stealing defences from stinging sea animals known as hydroids. You can read more about this video at KQED Science.

‘My God! Where’s the human voice?’ A charming reflection on our pre-recorded world

From to Siri to subways to customer service calls, pre-recorded and robotic voices are becoming an increasingly inescapable part of the human experience. In this short animation from StoryCorps, the US author, historian and broadcaster Studs Terkel (1912–2008) reflects on this trend away from human interaction and toward disembodied sentence fragments. Recalling a scene from a tram ride at Atlanta airport with exceeding wit and charm, he considers the richness of the human voice, and what we lose when it’s replaced.

From canoes to cities, a frenetic celebration of the power of indigenous Canadians

In her short film Mobilize, Caroline Monnet – a Canadian filmmaker and artist of French and Algonquin origin – uses archival documentary footage to honour the restless diligence of Canada’s indigenous people. Given access to more than 700 films from the National Film Board of Canada for the project, Monnet crafts a fervent visual collage that spans the country’s rural north, where indigenous craftsmen are seen fashioning canoes, to scenes from skyscraper construction in the urban south. According to Monnet, in making the film, she sought to explore the trajectory of her own family’s history, as well as to simply bombard viewers with ‘images of indigenous people kicking ass on screen’. Heightened by a feverish score from the Inuk artist Tanya Tagaq, Monnet’s film offers a deeply original and personal perspective on the indigenous Canadian experience.

This clever and stylish 1960 film is the most fun you’ll ever have at a physics lecture

Directed by the pioneering UK documentarian Richard Leacock, Frames of Reference is a slick and surreal dive into physics fundamentals and, in particular, why everything is indeed relative. Produced for high-school physics classes, the 1960 film features the physics professors Patterson Hume and Donald Ivey of the University of Toronto explaining, through an intertwined series of lectures and clever demonstrations, how frames of reference shape perspective. Using rotating sets, camera tricks and a visual style that suggests the film noir of Alfred Hitchcock, this is perhaps the most peculiarly entertaining half-hour physics lecture you’ll ever have.