Tools & Techniques

Dolphin Life: What we’ve learned in 40 years

Understanding how dolphins react to disturbances (like boats) is one aspect of behavior we study. Most recently, we’ve employed the use of drones in this research conducted in conjunction with colleagues from Woods Hole Oceanographic Institution (WHOI). Please don’t try this at home: We have special permits that allow us to use drones to study dolphins without harassing them. So please don’t try it on your own!

SDRP conducts the world’s longest-running study of a wild dolphin population, initiated in 1970. Information available from five decades of research on the multi-decadal, multi-generational, year-round resident community of individually identifiable bottlenose dolphins of Sarasota Bay established this as a unique natural laboratory for learning about the biology, behavior, ecology, social structure, health, and communication of dolphins, as well as the effects of human activities on them.

Long-term study is crucial for understanding the lives of members of long-lived species such as bottlenose dolphins, and for being able to detect trends in populations relative to changes in their environment. Knowing the long-term geographic range of a population unit allows the measurement of exposure to threats, which in turn facilitates mitigation, including direct interventions.

The ability to observe identifiable individual dolphins of known sex, age, and familial relationships through all of their life history milestones and associated transitions in behavioral and social patterns, to collect data on health and condition, and to then document their reproductive success and cause of death is rare in cetacean research.

This ability to closely monitor individuals also creates opportunities to develop and refine new research approaches and tools.

The SDRP has acted as a testbed for the development of many innovative methods to study marine mammals. The capture-release health assessments make it possible to attach gear to wild dolphins in a safe and controlled setting and also test the efficacy of things like performing ultrasounds in the field. Innovations occur in medical and veterinary research, as well as studies of dolphin behavior and communication.

Since 1975, Sarasota Bay has been used extensively for testing electronic tags, including radio-tags and satellite-linked tags, for tracking the movements and behavior of dolphins, leading to the very small transmitters used widely today. Digital acoustic archival tags (DTAGs), attached by suction cups for <24 hrs, were developed through tests of bottlenose dolphins in Sarasota Bay, providing a tool for studying communication in free-ranging dolphins, as well as responses to acoustic playbacks and boat approaches.

Data are collected through a variety of techniques, including systematic photographic identification surveys, focal animal behavioral observations, tagging and tracking, and passive acoustic monitoring from shore-based listening stations. Research is conducted under a series of Scientific Research Permits issued by NOAA’s National Marine Fisheries Service, and annual renewals of Institutional Animal Care and Use Committee approvals by Mote Marine Laboratory.