At the risk of prematurely bestowing the title, we believe we have discovered the strangest paper published in 2022. Scientists fitted GoPro cameras to the bodies of six dolphins trained by the US Navy and captured gruesome footage of them looking for food and devouring their kill. The objective of this potential invasion of dolphin privacy, according to the study, was to learn more about how the mammals hunted and ate.
Previously, scientists developed two contradictory ideas about how dolphins ate. They either ram fed (swimming faster than their prey and clasping the fish in their jaws as they overtake them) or suction fed (moving their tongues and expanding their throats to create negative pressure and slurp up prey). The researchers wanted to know which strategy dolphins employed, so they published their findings in the journal PLoS ONE on Wednesday.
“[S]ound and video have never been utilized together before to watch the activity of dolphins and the live fish they capture and consume,” the researchers said in their paper.
There’s also the truth that these dolphins were trained by the US Navy. The Marine Mammal Program, as it is known now, has been there since before 1960, when Navy researchers attempted to enhance torpedo design by studying dolphins. They have spent millions of dollars each year since then to raise and teach bottlenose dolphins and California sea lions. These creatures, according to the program’s website, “have outstanding low light eyesight and underwater directional hearing that allow them to locate and follow undersea targets, even in dark or murky waters”—and, unlike human divers, they don’t get the bends.
Nonetheless, the existence of a Navy program to train dolphins to detect objects such as deep-sea mines does not explain why this study was carried out. And, because Sam Ridgway, the study’s principal author and the Marine Mammal Program’s creator, died earlier this year, it appears that we will never know the answer to this critical question. We must instead adhere to the study’s text, which is nicely written in the style of dolphin fan fiction. Here’s a section that describes how the GoPro footage of the three dolphins hunting looked and sounded:
“The dolphin squealed as it seized, maneuvered, and consumed the prey.” If the fish escaped, the dolphin maintained the chase, and sonar clicks were heard less frequently than the final buzz and screech. The dolphins’ lips flared during capture, revealing virtually all of their teeth. The throat swelled outward. Even though the fish continued to swim away as they entered the dolphin’s mouth, the dolphin looked to gulp the fish right down.” — Ridgway and colleagues
The camera angles provide a view of dolphin side eye that we have never seen before and do not like to see again. Close inspection reveals that they are not bucolic Lisa Frank dolphins; rather, they are terrible, nightmare-inducing Roman dolphins who seem to love the excitement of the pursuit. The study, the 330th peer-reviewed article published by the Marine Mammal Program, describes how “it became obvious” when the dolphins picked their next target: The creatures began to move faster, as evidenced by an increase in the sound of the water as they passed through, and their heartbeats became apparent in the recordings.
It’s vital to note that this pseudo-horror movie material served a scientific purpose. The researchers discovered that the dolphins mostly suction fed rather than ram fed. “We were startled by all of our dolphins’ capacity to open their upper and lower lips to suck in food,” they wrote.
But hold on! The GoPro cameras also filmed a dolphin devouring sea snakes, which had never been seen before: “It is noteworthy that on one day, dolphin Z preyed on 8 yellow bellied sea snakes.” The dolphin clicked as it approached the snake, then took it in with a bit more head jerking until the flipping snake tail vanished and the dolphin squealed.”
You’re really welcome.