It’s good to be back home after our recent trip to Barataria Bay, Louisiana, where I, along with Lab Manager Jason Allen and Field Coordinator Aaron Barleycorn, assisted with a dolphin health assessment project as a follow-up to the Deepwater Horizon oil spill.

The data we gather from the Barataria Bay dolphins are being used for comparisons with dolphins in our Sarasota Bay reference population, as well as dolphins from Dauphin Island, Alabama, where a health assessment is planned for later this summer. These comparisons are being conducted with funding from the Gulf of Mexico Research Initiative through the Consortium for Advanced Research on Marine Mammal Health Assessments (CARMMHA) project, led by the National Marine Mammal Foundation. The information being gathered on the CARMMHA project is allowing a team of scientists, veterinarians and cardiologists to evaluate the long-term impacts and recovery of dolphins in heavily oiled bays and coastal waters.

This year, we provided opportunities for field tests of new cardiac assessment techniques in Sarasota and the CARMMHA team implemented them in Louisiana to help expand health evaluations.

Over a 10-day period in Barataria Bay, the team was able to gather health samples from more than 30 individuals that were briefly held for sampling and then released. While we cannot draw any final conclusions until all of the medical samples have been processed and analyzed, our initial impressions were that the dolphins of Barataria Bay continue to exhibit poorer health than those in Sarasota Bay.

We attached satellite-linked tags to many of these dolphins to determine if they continue to demonstrate the same strong site fidelity to Barataria Bay and vicinity as has been shown during previous years post-spill. 

The CARMMHA team was pleased to host Nicole LeBoeuf, Deputy Assistant Administrator for Ocean Services and Coastal Zone Management at NOAA’s National Ocean Service. In a follow-up letter after the assessment, she praised the CARMMHA team for its “dedication, unparalleled combination of exceedingly high talent, attention to detail, drive for scientific discovery, compassion for the animals, practical experience and priority for human safety… The sustained and dedicated work of you and your team is essential to filling our gaps in understanding the impacts of oil on marine mammals and the ecosystems in which they live.”

This study is truly helping us understand the impacts of oil spills in the lives of these dolphins and I’d encourage you to read more about these studies on our website .

Here's wishing you fair winds (that dissipate the red tide) and following seas!

Randy Wells

The CARMMHA 2018 Barataria Bay dolphin health assessment team at the Louisiana Department of Wildlife and Fisheries base of operations on Grand Isle. Photo by the National Marine Mammal Foundation.

We were heartened recently to receive a check for $17.01 to help support operations for the SDRP. It’s not the largest donation we’ve ever had, but coming from an after-school club of teens in Hancock, New York — “Girls on the Run” — we were pleased to see the next generation demonstrating so much care for the environment and the creatures that require healthy ecosystems.

The girls took on this fundraiser as a community service project, making posters, donation boxes and giving a presentation to their school on saving dolphins. We hope the girls understand that their sharing of information about the needs of the ocean and its creatures makes a real difference and we hope you’ll join us in applauding their support !

Closer to home, we’re dealing with another environmental issue — red tide, caused by the microscopic algae, Karenia brevis. While K. brevis is commonly found at low levels in Gulf waters, it can have devastating impacts when the cells multiply and form a harmful algal bloom. Red tides form many miles offshore and the reddish-brownish blooms travel inshore on wind and water currents. When K. brevis is present at levels that exceed about 100,000 cells per liter of seawater, and the cells break and release their powerful and potent neurotoxins, called brevetoxins, it can cause respiratory irritation among beachgoers, especially those who have underlying lung diseases, and it begins kill marine animals. Fish, seabirds, sea turtles, manatees and sometimes dolphins are affected.

The current red tide is affecting the coastline from Sarasota County south to Collier County and these counties are experiencing massive fish kills. Counts on Aug. 7 in Sarasota Bay exceeded 32 million cells per liter at Mote Marine Laboratory’s dock. Our regular monthly photographic identification surveys are observing dense concentrations of dead fish through much of the Sarasota dolphins’ home range. Over the course of these surveys we are collecting water samples and counting red tide cells in the samples, working with Mote to try to better define the extent and strength of the current bloom.

FWC is reporting 80 suspected red-tide manatee deaths between January and July 27 and there is currently a mass mortality event of sea turtles, with nearly 300 dead turtles reported and still others being treated by rehabilitation facilities for red tide exposure. To date, Mote has recovered four dead dolphins from south of our study area (none of them Sarasota Bay residents), and they are responding to reports of two more dead dolphins in the southern portion of the Sarasota dolphins' range.

Our prey fish studies earlier this summer prior to the arrival of the red tide indicate that fish abundance was at normal levels. Fish surveys during August and September, supported by the Barancik Foundation, will allow us to quantify losses of dolphin prey fish due to the red tide. In the 2005-06 red tide, more than 90% of some of the dolphins’ primary prey fish were lost.

An important part of conserving wild dolphins is understanding how changes in their environment impact their population. Some of our previous research has shown that dolphins changed their ranging and social patterns when prey availability declined during a red tide. They also interacted more frequently with humans — trying to take bait or catch from fishing lines, leading to the death of about 2% of Sarasota’s dolphins. Visit our website for more information on our red tide related research.

We don’t know what impact this red tide will ultimately have on the dolphin population in Sarasota Bay, or other dolphin populations along the Southwest Florida coast, but please be aware of a potential increase in dolphins attracted by your bait and catch while you’re out fishing. If dolphins do show interest, please reel in your line and wait for them to pass and/or change your location if you can do so without affecting the dolphins. If you’re releasing your catch, do so quietly, away from dolphins. (See more: Dolphin Friendly Fishing & Viewing Tips.

For the latest information on the red tide bloom and its impacts to our human population, here are some resources you can use:

Name: F256, also known as Jo Bob

Age: 11

Sex: Male

A Dolphin’s Life: We know this dolphin’s lineage back through five generations — he is the second calf of Little Orphan’s Annie, grandcalf of Bobby Jo, great-grandcalf of FB37 and great-great-grandcalf of Cathy. Jo Bob is the first-documented surviving fifth generation dolphin in the resident Sarasota dolphin community. Given that his grandmother, Bobby Jo, was orphaned when she was only 16 months old, it is amazing that this lineage continued this long. Bobby Jo’s mother died from a stingray barb, and Bobby Jo continued to survive on her own - she was not adopted by any other dolphins. At 11 years old, Jo Bob should be sexually mature soon and have the opportunity continue the lineage.

Jo Bob often chases fish toward seawalls, using the walls as a barrier to limit the fish’s movements so he can catch them. He likely learned this behavior from his mother and grandmother, who also used this technique.

The Sarasota Dolphin Research Program (SDRP) is a collaboration dedicated to dolphin research, conservation and education.  

 

It began in 1970 at Mote Marine Laboratory when Blair Irvine and high school student Randy Wells started a pilot tagging study to find out whether dolphins on Florida's central west coast remained in the area or traveled more widely. In 1974, with a contract from the U.S. Marine Mammal Commission, they were joined by Michael Scott and expanded the study with radio-telemetry.

 

Their subsequent discovery of long-term dolphin residency set the stage for today's efforts by demonstrating opportunities to study individually identifiable dolphins throughout their lives in a natural laboratory setting.  

Our work is conducted under the name "Sarasota Dolphin Research Program." This name ties together several organizations dedicated to ensuring the continuity of our long-term research, conservation and education efforts in Sarasota Bay and elsewhere.

The SDRP has been operated by the Chicago Zoological Society (CZS) since 1989. 

"Dolphin Biology Research Institute," is a Sarasota-based 501(c)3 nonprofit corporation established in 1982. It provides logistical support with research vessels, towing vehicles, computers, cameras, field equipment, etc. Since 1992, the program has been based at Mote Marine Laboratory on City Island in Sarasota Bay, with office, lab, storage and dock space and easy access to boat launching ramps within the home range of the Sarasota Bay resident dolphins.