The U.S. Navy has been taking the help of marine mammals to identify undersea mines, defend against enemy swimmers, and protect about a quarter of the U.S. nuclear stockpile. Recently, a team of researchers equipped some of the Navy’s dolphins with cameras and captured some phenomenal footage of the cetaceans hunting and feeding.
The dolphins are part of the Navy and are allowed to do open-water swimming. The recent project comprised six bottlenose dolphins (Tursiops truncatus) catching over 200 fish and sea snakes in a seawater pool and in San Diego Bay off the coast of California. The team’s research is published in PLOS One.
The cameras recorded audio and video over a six-month period. The audio helped them understand the way of communication among dolphins.
Some cameras were placed on the animals’ backs, giving a view of their blowhole, but others were on the animals’ sides, to best show their eyes and jaws.
“Fish continued escape swimming even as they entered the dolphins’ mouth, yet the dolphin appeared to suck the fish right down,” the researchers wrote. They ascribed that process to a method of feeding that toothed whales and other marine mammals use, in which the predator expands its throat to literally suck down prey.
The animals’ eyes rotated while swimming to track prey. Even when fish jumped into the air, the researchers observed the dolphins’ eyes swiveling, to chase their prey’s movement.
The dolphins consumed an array of creatures: bass, croakers, halibut, pipefish, and smelt amongst them. The open-water dolphins also caught sea snakes, jerking their heads to help the serpents down their gullets.
According to PBS, American Navy has been using dolphins in their projects since the 1960s. Dolphins were used by the Navy in Vietnam and the Persian Gulf. The program has been the subject of criticism, perhaps most notably by Ric O’Barry, a dolphin trainer who worked in the Navy’s dolphin program and released two of the program’s dolphins in 1996. Those two dolphins were later recaptured.
Other countries also have active military dolphin programs. In April, Russia deployed military dolphins to defend one of its Black Sea bases.