Dolphins, employed by the U.S. Navy to track down mines underwater, will be losing their jobs to robots in the next five years, the San Diego Union-Tribune reported.
According to the Union-Tribune, Navy officials say unmanned underwater vehicles--robots--can now do the same mine hunting jobs as the dolphins, but manufactured more quickly than the seven years it takes to train the animals.
Similar to security dogs, the Navy Marine Mammal Program-trained animals use their keen senses to detect underwater explosive mines and enemy swimmers. Dolphins' natural ability to locate underwater objects using sonar echolocation and to dive more than 500 feet without suffering decompression sickness known as the bends made them particularly well-suited to carry out important tasks for the military.
The Navy spends $28 million a year on its marine mammal program, headquartered in San Diego, where it employs and trains 80 bottle-nose dolphins and 40 California sea lions for activities such as object retrieval and port safety.
Of the 80 dolphins, only 24 of them do the mine-hunting jobs set to go to robots in 2017.
Still, the dolphins could be retrained for other kinds of work, including searching for bombs in places the 12-foot robots might not be able to do.
"About a quarter of [the dolphins] would be affected, but it's not like they are going to go jobless," said Mike Rothe, biosciences division head at the Space and Naval Warfare Systems Center Pacific in San Diego. "We have other assignments."
Until new technological developments allowing robots to do the mine-seeking work, the Navy used dolphins because their biological sonar was "unmatched by hardware sonars in detecting objects in the water column and on the sea floor."
In the operation of these systems, a dolphin waits to receive a cue from its handler before it begins to search a specific area using its biological sonar called echolocation. When a dolphin echolocates, it emits a series of clicks that bounce off an object and return to the dolphin, allowing a dolphin to construct a mental image of the object. The dolphin reports back to its handler, giving one response if a target object is detected and a different response if no target object is detected. If a mine-like target is detected, the handler sends the dolphin to mark the location of the object so it can be avoided by Navy vessels or dealt with by Navy divers.
Sea lions, with sensitive directional underwater hearing and low-light vision are excellent for detecting swimmers and objects underwater.
The Marine Mammal Program began in 1960, and dolphins have been used for military tasks since the Vietnam War. In addition to searching for explosive underwater mines, dolphins are trained to halt enemy swimmers attempting to plant explosives on American ships by signalling to their human trainers and "tagging" the enemy swimmer so Naval personnel can apprehend them.