The U.S. Navy's Marine Mammal Program has been around for more than 40 years.
Dolphins and sea lions are currently serving in the Persian Gulf where they help protect coalition forces. Theirs is the longest combat mission in the history of this special unit.
As The Early Show resident veterinarian Dr. Debbye Turner explains, about 100 marine mammals work as underwater allies.
In the early days of the Iraq War, Navy dolphins were deployed to clear mines from the port of Umm Qasr.
"Dolphins, with their echo-location capability to be able to look long-distance under water, and sea lions, with their great eyesight — five times better than yours and mine — so they can see in dark, turbulent waters," Marine Mammal Program director Michael Rothe says.
Half a world away in San Diego, Calif., new recruits are training for future missions.
"We start working with the dolphins born in our program in their first few weeks of life," animal behaviorist Mark Xitco says.
At their boot camp, for example, sea lions learn to attack a line to recover sunken objects. They can dive to depths of 1,000 feet.
Searching in extraordinary depths, looking for those objects, becomes a giant game of hide and seek.
The complex behavior begins with a simple training technique called targeting. Sea lions learn how to touch a target on command.
A dolphin's sonar is unmatched by man-made technology, making it ideal for finding mines. Although they will work in war zones, their missions are safe. Dolphins mark mines, but are too light to trigger an explosion.
Like other sailors, these sea cadets practice military maneuvers and must be physically fit to serve. The dolphins must submit to a daily health inspection.
"This is the first set of behaviors that they learn," says veterinarian Dr. Cynthia Smith. "We want to make sure at the beginning that we can get a good idea of their health status."
Smith starts with an inspection of the dolphins' teeth. They are taught to relax so that blood can be drawn, their temperature taken and their heart rate monitored.
"To get her heart rate, you're actually going to place the stethoscope bell under her pectoral flipper," says Smith as Turner listens with a stethoscope.
They also travel with a M.A.S.H.-style unit of specifically-designed medical equipment to monitor for illness.
Back at class, extra rations are rewarded for a job well done. Before graduation comes the final exam. Each recruit must master boarding the boat.
"It takes years to learn the skills ... to become part of our amphibious Navy where they can ride on ships, fly around on helicopters, be transported by a jet aircraft halfway around the world," Xitco says.
With a sea lion salute, the cadets are ready to report for active duty.
The Marine Mammal Program even boasts a Vietnam veteran. A female dolphin named Blank is still working for the Navy at the age of 47.
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