In our first ever footage from the perspective of dolphins hunting off the coast of North America, there is a buzz of clicks and joy.
The US Navy gave their dolphins permission to hunt in San Diego Bay after they were trained to help identify underwater mines and protect some of America's nuclear arsenal.
The marine mammals offered up exciting chases and even targeted sea snakes to the surprise of the researchers.
There are a lot of basic things we don't know about the popular and gross cetaceans.
Researchers broadly know of at least two techniques: slurping up prey like noodles from a bowl and ramming them down like hot dogs at a state fair.
The footage has more to say.
Six months of footage and audio were recorded by the cameras strapped to the bottlenose dolphins.
There were disturbingly odd angles of their eyes and mouths when the recording equipment was on their backs.
The dolphins are provided with regular opportunities to hunt in the open ocean, which gives them more time to eat fish. The NMMF marine mammal veterinarians say it is likely that these animals use the same methods.
They wrote that dolphins clicked at intervals of 20 to 50 milliseconds. Click intervals shorten into a buzz as you approach prey. After the fish was swallowed, buzzing and screeching ceased.
There were more than 200 fish caught by the dolphins. In desperation, the smelt flung themselves into the air.
The dolphins swam upside down to give them a clear view of what was happening.
The dolphins appeared to use both sight and sound. The dolphins were always looking for fish. Vision and echolocation seemed to be used together.
The sound of the dolphins' hearts as they pumped hard to keep up with the strenuous activities was recorded by the cameras, as well as the fact that they used suction to help gulp down their prey.
The dolphins mostly sucked fish in from the sides of their mouths with their tongues out. Negative pressure is created by their sucking muscles.
While dolphins have been caught messing around with snakes before, the footage confirmed for the first time that they may also eat these reptile as well.
A dolphin devoured eight sea snakes.
"Our dolphin displayed no signs of illness after consuming the small snakes," the researchers write, but they acknowledge this could be unusual behavior since the dolphins are captive animals"
The dolphin's lack of experience in feeding with dolphin groups in the wild may have led to the consumption of this outlier prey.
The lead author of the study died recently at the age of 86.
NMMF ethologist Brittany Jones told The Guardian that his approach to partnering with Navy dolphins would continue to educate and inspire future scientists.
The navy trained dolphins work in open water almost every day. Over the years a few have decided to swim away. Almost all stays.
The research was published in a peer reviewed journal.
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