In the reefs near a group of French Polynesian islands in the South Pacific, Echo is a young and playful bottlenose dolphin who isn't like the rest of his pod.

If anyone who watches the film comes away thinking, 'if you live in the ocean, you need friends', that for us is a success story.

Then, we hope that will translate into you can't just start overfishing certain species because the community will not survive if you kind of do that.

Its "making-of" documentary, Diving with Dolphins, revealed that in the three years of production of the film, one-third of the reef used on location died.

[9] Disneynature had invited her to a screening of one of their previous projects, back when Portman was living in Paris, and she brought her child along for the viewing.

[7] In her 20s, she learned to scuba dive with dolphins (off the coast of Eilat, Israel, situated on the Red Sea) and was excited to join the cast.

[10] Keith Scholey is the director, who also directed Disneynature's Bears,[11] and Roy Conli is its producer.

[8] The filming was done in French Polynesia, Hawaii, and Florida by cinematographers Roger Horrocks, Paul Atkins, Didier Noirot (who previously worked on Jacques Cousteau's crew) and Jamie McPherson.

[8] As it is impossible to follow a dolphin for an extended amount of time, cinematographers would film as long as they could, gathering thousands of hours of footage.

The editing team (led by Martin Elsbury)[12] then pieced together a narrative that, according to Scholey, is "true to the life of a dolphin".

[15] Owen Gleiberman with Variety called the film "a puckish, bedazzling, and memorable entry in the Disney nature canon".

[16] Frank Scheck of The Hollywood Reporter commented on the film's "gorgeous cinematography and canny editing typical of Disney nature docs as well as Portman's soothingly lighthearted, bedtime story-style narration that turns serious at just the right times".

[17] Steve Pond with TheWrap called it "the Goodfellas of nature docs", saying "'Dolphin Reef' is a satisfying entry in the Disneynature slate, albeit one where the dolphins in the title are upstaged by some of their supporting cast, and the reef itself is even more spectacular than the creatures who get the most screen time".

[9] In his review, Daniel Rutledge said the film was "the delightful, wondrous joy", adding that "Natalie Portman is ideal as the voiceover star", and "the photography is also consistently brilliant with the camera operators getting right up amongst the dolphins and whales and in amazingly tight on the little coral creatures".

[20] Steven Price (of Gravity, Our Planet, and Suicide Squad) composed the film's original score.

[21] He also noted that, historically, Disney has produced nature films as "family-based thing", but that this story focused on being ecologically sound, about "the interconnection of everything", and character driven.