HONOLULU -- The U.S. Navy recently unveiled new technology that could put military mammals out of a job.

The new vehicles can dive to depths of nearly 2,000 feet and stay underwater for 70 hours -- but more importantly if something goes wrong in dangerous waters -- they can be replaced while Navy dolphins can not.

Dolphins are a big draw for marine life lovers, but along with the seemingly fun and frolicking these mammals are also important tools for the U.S. Navy.

"They had various use of dolphins, mainly mine detection. Unfortunately, you are putting dolphins at risk," said dolphin advocate Kenneth LeVasseur.

For decades, the military relied on the intelligent creatures to gather intelligence underwater, as well as complete other missions.

"The U.S. Navy uses dolphins like super SEAL operatives. If you want a human to go underwater the best is a U.S. SEAL. If you want better, then you use a dolphin," LeVasseur said.

However, as countries practiced on the open ocean during Rim of the Pacific 2010 -- closer to Hawaii, Marines were on a different mission to test this unmanned underwater vehicle, or UUV.

"These vehicles are equipped with sonar that can do some of the mine countermeasure missions," said Todd Webber, with the Space and Naval Warfare Systems.

The UUVs, which look like mini-submarines and are computer controlled, could one day replace human and Navy-trained mammals, like dolphins and sea lions, to map underwater mine fields. Each can transmit that important information even from the ocean depths.

"It gives us data like GPS, speed, heading," said Jim Bass, with the Marine UUV Platoon.

Its high-tech expensive equipment, but it could signal a wave of change for the Navy -- one that dolphin advocates have been pushing for many years.

"Hopefully they will shut down dolphin program and go with less expensive more expendable program," LeVasseur said.

During RIMPAC, divers lay training mines to test the UUVs ability to locate them. Now the Navy is analyzing the effectiveness of these new tools.