First of its kind underwater video reveals secret lives of wild dolphins

Footage recorded off the coast of New Zealand reveals a first look at wild dolphins' lives in the absence of humans.

The camera, strapped behind the dolphin's dorsal fin, has recorded rarely seen behaviour in wild dolphins, including how mothers and their calves interact, how dolphins play with kelp, sexual behaviours and social behaviours such as flipper-rubbing. A total of eight cameras were attached to wild dusky dolphins using suction cups, with the results published in a paper published in the journal Marine Biology.

The cameras had memory cards, high frequency and satellite transmitters, time and depth recorders and a battery life of six hours. Attaching the cameras firmly but without hurting the dolphins was a challenge, as the agile and fast-moving animals could quite easily brush it off while swimming at speed.

"For the first time, these cameras have given us the opportunity to see what dolphins do on their own terms," said study author Gabriel Machovsky-Capuska of the University of Sydney in Australia.

The camera is a prototype designed to test the possibility of recording wild dolphins' activities without a human camera crew. However, the total 535 minutes of underwater footage recorded have already recorded behaviour never seen before using traditional filming techniques.

"There were no wildlife crews, no invasive underwater housings – and the dolphins remained largely unaffected by our cameras," said Machovsky-Capuska.

Scientists hope the films will reveal clues useful for dolphin conservationists, with information about the animals' prey, behaviour and habitats to help protect endangered species. For example, filming from a wild dolphin's perspective could reveal the impact of shipping and coastal development.

"From the surface, researchers can only see about 10 per cent of what is going on in an animal's life. With these video cameras, we can 'see' from the animals' perspective and begin to understand the challenges they face as they move throughout their habitat," said dolphin specialist Heidi Pearson of the University of Alaska Southeast in the US.

Machovsky-Capuska added: "This research opens up a whole new approach for capturing wild animal behaviour, which will ultimately help us to not only advance conservation efforts but also come closer to understanding wild predators' and human nutrition too."