[MARINE_BIOLOGY_INTERNATIONAL] Do "shouting" dolphins need more fish?

(Santa Cruz Sentinel)

Measuring the metabolism of a dolphin at heart of Seymour Center study

By SHANNA MCCORD
Posted: 11/22/2010 01:30:50 AM PST

Marine Mammal Physiology Project head trainer Beau Richter talks about... (Shmuel Thaler/Sentinel)

SANTA CRUZ -- If a dolphin makes an increasing amount of noises to communicate with his marine mammal brethren, does that mean he's using more energy and therefore needs to consume more fish?

That's one of the theories being studied by marine biologists at UC Santa Cruz's Seymour Center at Long Marine Lab. The study was explained Sunday to an audience of about 100 people during a lecture called Marine Mammals: The Physiology Project.

The importance of knowing more about dolphins' metabolism was laid out in layman's terms by head trainer Beau Richter.

"Our oceans have become very noisy," Richter said. "To compensate for that, animals are increasing the intensity of their vocalizations. It would be like being in a loud restaurant for us. The cost of that energy is that they have to eat more and there's less fish to feed humans. It's a delicate balance."

Richter introduced, through photos and videos, the two bottlenose dolphins -- Puka and Primo -- scientists at Long Marine lab are working with to study various behaviors that affect their metabolisms.

He showed the dolphins outfitted in an O'Neill vest made of the same neoprene material wetsuits are made with. The vests, he said, are they only way the dolphins can carry the equipment necessary to measure their heart rates.

The dolphins wear the vests when scientists are investigating the change in metabolism as it relates to deep diving and oxygen consumption, Richter said.

"We have them dive down and rest, dive down and do moderate exercise and dive down and do a high level of exercise," he said. "What have we learned so far? The equipment works. We also want to find out if marine mammals can suffer the same pressure-related illnesses that human divers can suffer, such as the bends."
Marine biologists are also studying a rare and endangered Hawaiian monk seal, Ho Ailona, who arrived to the lab last November.

"Not much is known about these guys," Richter said.