Castaway Participates in Hearing Test

Posted on: April 10, 2009

Castaway participates in her first hearing test at Dolphins Plus! Audio evoked potential(EPA) testing is a non-invasive means of testing a dolphin’s hearing. EPA can be used to test the entire frequency range of hearing in a dolphin within a single test session. This form of testing hearing allows for animals that are deaf, such as Castaway, to have their hearing tested as well.

Through EPA, the dolphin's hearing is tested by measuring the electrical activity generated by the brain in response to a sound. The sounds are computer generated and played for the dolphin through speakers, called "jawphones", placed by suction cups against the dolphin's lower jaw. The lower jaw is where dolphins would receive sound in their day to day lives. The dolphin's response is measured by computer analysis of electrical activity in the dolphin's brain which is received through a collection of transducers on the dolphin's head.

The sense of hearing is the most important of the senses to dolphins because of their use of sound to communicate, hunt, maintain social bonds and navigate. Identification of hearing problems allows behavioral issues to with training to be better explained. This knowledge helps the animal care staff to modify animal care and husbandry procedures and potentially increase the overall quality of care for Castaway.

Castaway preformed the EPA test with flying colors. She remained calm through-out the 52 minute test and seemed to be enjoying all of the extra attention. The animal care awaits the results of the hearing test in the up coming weeks!