When three juvenile bottlenose dolphins died near the Kingfish Boat Ramp in November 2018, they were identified as fifth-generation Sarasota Bay dolphins.
But what does that mean?
The Sarasota Dolphin Research Project was the point of reference. SDRP is conducting the longest continuous study of marine mammals in the world.
Generations of dolphins in the waters surrounding Anna Maria Island have been identified and followed by research scientists who call Sarasota Bay their living laboratory.
Blair Irvine, who serves on the board of directors for Dolphin Biology Research Institute in Sarasota, and a then-high school student named Randy Wells, started the project in 1970.
The driving question of that time?
Do dolphins live here all the time or do they pass through?
Almost 50 years later, researchers know the dolphins do live here, generation after generation, Wells told The Islander.
Wells is the director of the Chicago Zoological Society’s SDRP and works from an office at Mote Marine Laboratory.
The project research encompasses husbandry, threats to dolphins from environmental issues such as the recent red tide, common illnesses, what and where dolphins eat and how far they move about in their home range.
The CZS took over the SDRP in 1989. The CZS, based at Brookfield Zoo in Brookfield, Illinois, was the first inland oceanarium to contain live dolphins in the United States, adding them in 1961.
“We had no idea where the dolphins lived when we started. We knew nothing about the local resident community,” Wells said.
Now, the project is studying a fifth generation of Sarasota Bay dolphins.
With long-term surveys developed along the way, scientists have learned about dolphin social behavior, habitat needs and the impact of humans on dolphin’s lives and health.
Veterinary knowledge from the project has been used worldwide to develop protocols on treating sick and injured dolphins.
The outlook for Sarasota Bay dolphins
Wells said long-term, the outlook for the bay dolphins is guarded.
“It’s all because of the red tide,” he said. “We lost residents in the program from 45 years old to the juveniles at Anna Maria that were about a year and a half old. But it’s the long-range effects we are concerned about.”
Wells said after a severe red tide event in 2004-05, prey fish declined 90 percent for the Sarasota Bay dolphins.
This resulted in increased dolphin mortalities in 2006, including a 2 percent jump in fishing-related deaths caused by dolphin interactions with anglers.
Wells said as available fish become scarce, dolphins often turn their attention to anglers for an easy meal.
“Don’t feed dolphins, ever,” he advised. “If dolphins do approach you while you have fishing lines out, reel them in and move locations. Do not release fish when dolphins are close by.”
Now, with the 2018-19 bout of red tide, Wells said, “we are seeing the same 90 percent decline in prey fish now.”
“We may not know the outcome for a year or more on the Sarasota Bay dolphins mortality,” he said.