Q&A: The Mystery of Saltwater Dolphins Swimming Upriver to Clay County

UNF Expert Quincy Gibson Explains Why That May Be a Bad Thing

A dolphin swims in the St. Johns River. (Photo by Dr. Quincy Gibson, director UNF Dolphin Research Program under authorization of NOAA GA LOC #23796)

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A few weeks ago in the late afternoon, my wife and I were driving east across the Shands Bridge when out of the corner of my eye I saw a lone dolphin casually swimming on the south side of the bridge heading toward Palatka. 

“Dolphin!” I shouted.

My wife looked up from her phone immediately after the lone dolphin dove.

Flat water. No dolphin. Awkward driving pause.  Look of skepticism on my wife’s face.

Then the dolphin surfaced for a breath. “Dolphin, dolphin!”  she shouted.

We looked at each other like we had seen some kind of alien species. 

I’m a long-time resident of NE Florida and spend a good amount of time on the water. I’ve seen a lot of dolphins in the St. John’s River, but I have never witnessed one south of the Buckman Bridge, so the sighting was unusual. 

When we got home, I texted a friend who had been a longtime Florida Fish & Wildlife officer in Putnam County. I asked him if he had ever seen a dolphin in the St. John’s River between Palatka and the Shands Bridge. He quickly responded he had not despite having spent a lot of time on the river during his career. 

Since there had been no sightings of alien spacecraft or reports of crop circles out in Clay Hill, I figured I should investigate a little further.

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After a quick google search about dolphins and the St. John’s River, I discovered a local river dolphin expert, Quincy Anne Gibson, associate professor at the University of North Florida and director of the UNF Dolphin Research Program. 

I emailed Dr. Gibson, told her about my dolphin sighting south of the Shands Bridge, and asked if something like this was rare and unusual. She responded that it was rare, but not unusual.

I was hooked and I needed to know more about why this lone dolphin had been swimming past Clay County and heading toward Palatka. She agreed to an interview. 

Dr. Quincy Gibson, director UNF Dolphin Research Program.

Mike Michel: Is it rare and unusual to see St Johns River Dolphins south of the Shands Bridge and why would a dolphin be in this area swimming by Clay County heading south toward Palatka?

Dr. Quincy Gibson: It is rare and unusual to see a St Johns River Dolphin really south of downtown Jacksonville. During the summer there can be over 500 dolphins in the St Johns River and the majority of these dolphins are consistently sighted between Mayport and downtown Jacksonville. Why a dolphin would be as far south as Doctors Lake or the Shands bridge is puzzling, but there are possible explanations.

First, St Johns River dolphins are intelligent and curious animals, and it could be that this individual dolphin was sort of an adventurer and just exploring the river.

Second, that dolphin could have been sick and disoriented and got lost. Over the past decade plus, there were two separate unusual mortality events (UME) that impacted St. John’s River Dolphins. One in 2010 was due to an undetermined cause. One from 2013-2015 was due to a morbillivirus epidemic along the entire eastern seaboard.

During this epidemic there was a Doctor's Lake sighting and stranding. We know viruses can affect a dolphin's ability to navigate safely in their habitat and sometimes lead to a dolphin getting lost and/or stranded.

Lastly, our St. John’s River Dolphins are not healthy. Many have skin lesions and look emaciated. On some of our dolphins, including mothers with calves, you can see their ribs through their skin. These dolphins are basically starving, and it could be that our river dolphins are having to shift their habitat to follow their prey. 

Michel: When you say the dolphins may be shifting their habitat, how far south can our river dolphins safely go?

Gibson: Our river dolphins routinely move back and forth between high and low salinity areas and seem to be able to tolerate temporary salinity fluctuations. High salinity areas are those closer to the Mayport jetties and lower salinity areas are those areas closer to downtown Jacksonville. River water south of downtown Jacksonville is basically freshwater and freshwater is toxic to dolphins.

If a dolphin spends too much time in freshwater they start to experience physiological symptoms—for example, organ failure—and they can become disoriented. I would expect that our river dolphin population stays between Mayport and downtown, but we may see dolphins occasionally going south into freshwater in search of prey.

Michel: What can the local population, the boaters, and fishermen on the St. John’s River do to help the UNF Dolphin Research Program?

Gibson: It’s always an exciting experience to see our river dolphins in their natural habitat. If you can get a picture of the dolphin’s dorsal fin and send it to me at quincy.gibson@unf.edu I may be able to identify the individual dolphin. And if you can include the location of where you saw the dolphin that will also help us with our habitat research. I would ask, though, that boaters be cautious when around dolphins and try and stay at least 50 yards away from the dolphins.

The St. John’s River is a very noisy river and dolphins primarily rely on their hearing to avoid boats. The noise masks the sounds of approaching boats and dolphins could surface very close to a boat and its motor. If you see dolphins close to your boat, it’s best for safety to put your engine in idle. Also, if you are fishing and see dolphins near your fishing lines it’s a good practice to reel in your bait until the dolphins leave your area to avoid a dolphin trying to take a fish you have hooked and in turn getting hooked themselves. If you encounter an injured or stranded dolphin call the FWCC hotline at 1-888-404-3922.

UNF Dolphin Research Program on weekly St. John’s River Dolphin Survey

It was amazing to learn that local experts can actually identify an individual dolphin in our area by the fin on its back. As I reflected on seeing that lone dolphin swimming in our area, I hoped it was just exploring the river shores of Clay County and prayed it was not sick or starving.

If you are interested in learning more about our St John River dolphins, you can read about the UNF Dolphin Research Program here.

If you would like to help their research financially, you can donate by symbolically adopting a local dolphin. The basic adoption is $40 and the special “Name Your Dolphin” adoption donation is $80. Upon adopting a dolphin, you will receive an adoption card, a 5 x 7 photo of your adopted dolphin, and information about him/her.

All donations are tax-deductible and proceeds go directly to UNF’s Dolphin Research Program. To adopt a dolphin and support UNF research, contact Dr. Quincy Gibson at quincy.gibson@unf.edu.