Spotted seal study reveals sensitive hearing in air and water

Date:

February 26, 2014

Source:

University of California - Santa Cruz

Summary:

Two spotted seals orphaned as pups in the Arctic are now thriving at UC Santa Cruz's Long Marine Laboratory, giving scientists a rare opportunity to learn about how these seals perceive their environment. In a comprehensive study of the hearing abilities of spotted seals, researchers found that the seals have remarkably sensitive hearing in both air and water. "We wanted to develop a better understanding of how Arctic seals use sound in their environment and how human intrusions and other changes in that environment may influence them," the lead author noted.

Continued

Manatee Mystery: Why Can't They Avoid Speedboats?

Manatees have sensitive hearing, but that doesn't necessarily keep them safe from passing boat propellers, a new study finds.

These docile sea cows have no natural predators in their coastal U.S. habitat, but fast-moving speedboats and other watercraft are a danger. Collisions with boat hulls or propellers can severely wound or kill a manatee.

Researchers have long questioned why manatees can't seem to effectively avoid boats. The animals' vision is bad, so researchers from Mote Marine Laboratory and Aquarium turned to the question of how well manatees hear.

Mote researcher Joe Gaspard and colleagues tested the auditory abilities of two aquarium manatees, Buffett and Hugh, both of which are trained to participate in behavioral research. The researchers had the manatees swim to a "listening station" underwater and then had them touch a yellow paddle when they heard a sound. A correct response earned the manatees a reward of fruit or veggies.

Continued:  http://www.livescience.com/19639-manatee-hearing-boats.html