Evaluating the Extent of Pressure and Level of Harassment Exerted on Bottlenose Dolphins (Tursiops truncatus) During "Swim-With" Tours in Panama City Beach, FL
Abstract
Federal and state management agencies have attempted to address the harassment and
illegal feeding of wild dolphins in the United States, but few studies have evaluated
the efficacy of these interventions. In 1998, Samuels and Bejder conducted a study
contracted by the Marine Mammal Commission to document the number of dolphins affected
by illegal feeding and harassment in Panama City Beach, FL. Since the results of their
study, more resources have been allocated towards increasing the presence of undercover
officers on dolphin tour boats, fines have been issued for counts of illegal feeding,
and there has been an increase in education and outreach efforts.
The present study reevaluates the current level of harassment and illegal feeding
towards dolphins in Panama City Beach, FL, which can be used as a comparison to the
work of Samuels and Bejder and subsequent management actions. In the study, I conducted
10 hours of detailed observations over five days to quantify the number of vessels
and swimmers surrounding dolphins during tours, assess the type and frequency of harassment
behaviors in the presence and absence of Marine Patrol vessels, and discuss dolphin
responses to harassment behavior.
On average, I recorded 1.4 boats, 1.1 jet skis and 0.7 swimmers surrounding an individual
dolphin. The most common harassment behaviors included chasing, luring and corralling
dolphins. The frequency of harassment was significantly greater when the Marine Patrol
was absent; I observed 75 harassment behaviors in their absence and only six in their
presence. Lastly, most dolphin responses observed were expected from the conditioned
status of that animal.
These findings suggest that dolphins are rarely alleviated from anthropogenic pressure
during tours and that harassment and illegal feeding is still prevalent, however,
significantly lessened in the presence of Marine Patrol. These results and conclusions
offer a benchmark to inform future management actions under the Marine Mammal Protection
Act.
Type
Master's projectPermalink
https://hdl.handle.net/10161/8510Citation
Machernis, Abigail (2014). Evaluating the Extent of Pressure and Level of Harassment Exerted on Bottlenose Dolphins
(Tursiops truncatus) During "Swim-With" Tours in Panama City Beach, FL. Master's project, Duke University. Retrieved from https://hdl.handle.net/10161/8510.Collections
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