Something's changed for the river dolphins

The bottlenose dolphins of the St. Johns River have a favored spot where they like to hang out, frolic, eat and socialize. It's near the BEA Systems dry dock, east of Blount Island and just west of where the Intracoastal Waterway comes up from the south and meets the St. Johns.

The animals seem to like it there, even though on a recent sunny weekday morning it was hardly a bucolic little hideaway. Instead, it was more like a watery superhighway, sprinkled with dolphins.

Power boats zipped by, some stopping to take in the dolphins' antics. An air-boat full of tourists came in for a look. Two jet-skis raced through, heedless. Everyone moved aside as a giant red container ship came marching imperiously down the middle of the river. Just overhead, a helicopter buzzed by.

A little to the west were two big dredges, not at work at that moment but still hard to miss — visible reminders of a multi-year plan to deepen the river to provide for even bigger cargo ships.

Dolphin researchers at the University of North Florida have been trying to figure out if the river dredging is hurting the St. Johns' 300 or so dolphins, the 150 who call it home and the 150 who visit it seasonally.

Quincy Gibson, head of the school's Dolphin Research Program, said it's likely dredging is having some ill effects on the dolphins, but research is still going on and it's hard yet to state that conclusively. There could be natural changes or other factors that come with the animals trying to live in such a highly urbanized and heavily trafficked area.

“We know the dolphins are still using the areas where the dredges are located. Is their habitat being degraded?" she said. "Probably. But being able to demonstrate that is really challenging."

There are warning signs, though, that something has happened to change their food supply: "Skinny dolphins, emaciated dolphins, is kind of becoming the norm for us,” Gibson said.

She noted that necropsies on dolphins have turned up many with empty bellies and some with skin lesions that indicate a compromised immune system.

“I used to joke that if I were a dolphin, this would probably be the last place I would choose to live,” Gibson said. But partnerships with other dolphin research groups in Florida show that, from the Georgia border to the Indian River in Brevard County, the St. Johns holds more estuarine bottlenose dolphins than anywhere else.

"There’s something about our estuary that’s really critical for dolphins, and it’s bringing them in," she said.

The research boat of UNF's dolphin program makes regular trips from Mayport into the river. The scientists aboard have, over a number of years, identified and tracked the St. Johns' resident dolphins through countless photographs and cataloguing.

They've been able to get a window into the active lives of the dolphins, which center on sex and violence, caring and frolicking, shifting alliances and longtime companionships — a regular soap opera with a big cast of characters.

Kristy Brightwell has been on the water for six years, and feels as if she knows those dolphins. She started as a graduate student researcher, then became a visiting lecturer at the school and lab manager for the dolphin program.

A trip on the river last week was her last though: She's taking a job with the state in Tallahassee, working as a manatee data analyst with the Fish and Wildlife Conservation Commission.

Over the years, she's taken thousands of photographs as dolphins surface nearby. She can recognize most immediately by identifying features such as their distinctive dorsal fins, and calls out their names (most have names) or, if they're still nameless, their identifying numbers. The dolphins seem to know the research vessel, which moves slowly and cautiously as it approaches each group.

Catherine Yeoman, an undergraduate from the University of Northern Iowa who's spending her summer studying in Florida, carefully logged each detail — including Brightwell's repeated observation of "visible ribs." In other words, some of these dolphins were not getting enough to eat.

Emily Szott, a graduate student, piloted the boat. Also aboard were undergraduates Caroline Caron and Joey Lappin. They began spotting dolphins, year-round river-dwellers and seasonal ocean dolphins, almost as soon as the vessel left Mayport.

That's a welcome change from earlier trips, where sightings there, for some reason, were sparse. "It's really good to see them right here again. It’s been a while,” Brightwell said.

The boat then headed west, toward the BAE drydock, where dolphins were plentiful, despite the heavy traffic. They like the wall of the dry dock since they can herd fish against it for easier eating. But on the long ride there from Mayport, there was not a dolphin to be seen — and that's not normal.

“On a normal summer survey, we will just be going from group to group consistently up river, just a few minutes between each sighting," Brightwell said. "This summer there’s definitely been a change."

She too was reluctant to state conclusively why things are different, but it's clear, she said, that's something happened to change the patterns of dolphin life there.

Brightwell — who was leaving that afternoon for her new job in Tallahassee — talked about some of the dolphins she's gotten to know so well the last six years.

There's Miziwa, a mother, whose offspring are often hyper. You can see them coming from a long way away.

There's Tessie, daughter of Athena, who has some attitude issues. "You'll see a dolphin, it seems like it’s having a hissy fit, it'll be tail-slamming, body-slamming the water, I'll know that’s Tessie. We get close, and sure enough it’s her. She’s a little grouchy.”

Then there's her favorite, a male named Loki. He's had some big changes in his relationship status: As people say, it's complicated.

He was in a long-term alliance with another male named Thor. Think of it as a bromance, which with dolphins can last decades. Together, Loki and Thor teamed up to try to persuade female dolphins to mate with them. Sometimes they got together with Duval and Jax, two dominant males, to make it a more powerful foursome.

Then along came a dolphin named Odin. He and Thor seemed to hit it off, so Loki was kicked out of the group.

Good news though: He seems to have found a new friend and wingman in Neptune, who had been alone for several years since this ally, Zeus, disappeared. Now Loki and Neptune are together — and just the other day Brightwell saw the two of them working together to herd a female.

“Loki lost his best friend Thor, but he got a new friend, Neptune. So that’s good. It adds to the social complexity," she said. "Just as they get kicked out, they can establish bonds with others."

Brightwell, after this last trip of hers, standing by her car in the marina parking lot, said she's going to miss them all. “It’s strange," she said. "It does not feel like I won’t be back here tomorrow.”

Matt Soergel: (904) 359-4082