Navy dolphins and sea lions

A trained California sea lion practices attaching a clamp to a simulated mine on a dock in San Diego. (Don Bartletti / Los Angeles Times)

March 29, 2015 10:46 AM PT

In San Diego, the Navy has 90 dolphins and 50 California sea lions in a program run by the Space and Naval Warfare System Pacific. The dolphins and the sea lions, using their keen eyesight and “biological sonar,” are expert at finding mines.

At a training base in San Diego, a California sea lion wears a sling equipped with devices for mine sweeping, swimmer detection and object recovery. (Don Bartletti / Los Angeles Times)

Bottlenose dolphins face their trainers from an open-air pen at the Naval Mine and Anti-Submarine Warfare Center in San Diego. The Navy has 90 dolphins that are trained to use their keen eyesight and “biological sonar” to find enemy mines. (Don Bartletti / Los Angeles Times)

A bottlenose dolphin leaps onto a recovery boat at the Navy’s base for training marine mammals. Dolphins and California sea lions are trained in San Diego for mine sweeping, swimmer detection and object recovery. (Don Bartletti / Los Angeles Times)

Wearing a harness equipped with a camera and sonar devices, a bottlenose dolphin slides onto a beaching tray in San Diego in preparation for transport to the open sea. (Don Bartletti / Los Angeles Times)

The Navy trains bottlenose dolphins and California sea lions in San Diego for mine sweeping, swimmer detection and object recovery. (Don Bartletti / Los Angeles Times)

An 11-foot-long unmanned underwater vehicle is lifted onto a launch boat at the Naval Mine and Anti-Submarine Warfare Center in San Diego. The craft is part of a Navy program that also uses trained dolphins and sea lions to detect enemy mines and submarines. (Don Bartletti / Los Angeles Times)