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Sarasota Dolphin Research Program continued

Other health or survival issues may One of the program’s most interesting In the sea, where underwater vision is
be much more noticeable to a casual areas of collaborative research has been often limited, dolphins need an incredible
observer. Dolphins swimming near shore in acoustics. The team continues work sense of hearing, and their auditory
sometimes come into contact with boat with internationally acclaimed scientists capabilities are nearly eight times more
propellers. Or dolphins are sometimes fed who have pioneered the study of dolphin acute than in people. However, high
by well-meaning but misguided boaters or communication, including confirming levels of manmade noise can negatively
anglers, thereby encouraging these animals and expanding upon the groundbreaking impact their hearing. Any hearing loss
to take risks that lead to entanglement discovery that individual dolphins have is particularly harmful to them because
in, hooking by, or ingestion of fishing signature whistles that serve as “names.” they rely heavily on this sense to hunt
gear or to greater exposure to spinning Aiding in this research have been the and communicate with each other.
propellers. Feeding wild dolphins is Sarasota program’s health assessments, Researchers working with the Sarasota
illegal under the federal Marine Mammal during which scientists have engaged in program use noninvasive techniques
Protection Act. The Sarasota program communication playback experiments, that are very similar to those used to
advocates for measures that help people observing how dolphins respond to assess hearing for human babies. They
understand the impacts of their actions whistles from other dolphins, as well as place a suction cup containing a speaker
and mitigate these harmful scenarios other sounds. As an extension of this work, on a dolphin’s lower jaw, which acts as
while seeking solutions that help people scientists recently conducted playbacks to a sound conductor, and play tones of
toresponsibly enjoy the coastal ecosystem. free-swimming dolphins while obtaining various frequencies and sound levels. The
overhead drone video of responses. dolphin’s brain responds to the tones in
different ways, and those responses are
recorded. The data show that manmade
noises are not having a detrimental
impact on the hearing of bottlenose
dolphins living in Sarasota Bay. But
the situation could be very different
in offshore waters, where dolphins are
exposed to extreme noise from powerful
naval sonar, ship traffic, and seismic
airguns used for oil and gas exploration.

An intern helps Society scientists collect
data on individually identiable dolphins.

26 GATEWAYS | UNDERSTANDING DOLPHINS BY LEAPS AND BOUNDS