Harbor Branch teams find visible disease in 8 of 18 dolphins examined from lagoon
STORY BY STEVEN M. THOMAS, (Week of July 5, 2012)
The 1,000 bottlenose dolphins that live in the Indian River Lagoon were already the most studied dolphin population in world at the beginning of summer. Now, after 10 days of intensive fieldwork by 115 researchers that wrapped up last Wednesday, another powerful layer of data has been added to scientists’ evolving picture of dolphin existence.
“I am really excited and optimistic about the information we gathered,” says Adam Schaefer, an epidemiologist at Harbor Branch Oceanographic Institute who studies dolphin health in part to understand environmental threats to humans.
“We have gathered a voluminous amount of data,” says Stephan McCullock, who manages HERA – the Dolphin Health and Risk Assessment program – at Harbor Branch, which began in 2003 and has included detailed medical examinations of more than 200 lagoon dolphins.
“What we are doing is a very rare thing,” McCullock says. “It is one of only three programs of its kind in the world. It is the pinnacle of dolphin research.”
The science taking place in the estuary is truly exhilarating – more than 60 peer-reviewed scientific papers have been published about the work and experts come from around the world to participate in the annual exams – but the results of the research are grim.
HERA has shown that dolphins in the Indian River Lagoon suffer from a bewildering array of viral, bacterial, fungal and cancerous diseases that are a direct result of what scientists call “environmental stressors,” which mostly means human pollution such as mercury, prescription drug residue and poisonous fertilizer runoff. Climate change likely plays a role, too.
“Eight of the 18 dolphins we examined this year had visible signs of disease,” says Dr. Juli Goldstein, a veterinarian and Florida Atlantic University assistant professor who oversees the medical exams. “There is drastically more illness and disease than there would be among a healthy dolphin population. It is extremely concerning for the sake of the dolphins and perhaps even more so for us because they are a sentinel species on this coast. If they are getting sick, we are next.”
This year’s HERA fieldwork began June 18 and finished June 27.
Despite wild weather along the margins of Tropical Storm Debbie, McCulloch and his international team caught and examined 18 dolphins, operating under a permit from NOAA – the National Oceanic and Atmospheric Administration.
“We had 14 boats and 85 to 90 people on the water each day,” says McCulloch. The group worked out of Harbor Branch and captured and examined dolphins along a 40-mile stretch of the lagoon between Jensen Beach and the Sebastian Inlet.
“We met at the dock around 6:30 a.m. and were out for 10 or 12 hours,” says Schaefer.
Dolphins were corralled with float nets and brought aboard what Goldstein calls “a shaded floating examine room.”
Researchers took blood, urine, feces and blubber sample as well as stomach contents, swabs from blow holes and other samples.
“We numb them with anesthetic before taking blubber samples,” says Goldstein. “It is similar to a doctor doing outpatient surgery.”
Goldstein says the dolphins tend to be “surprising calm” during the 45-minute examinations.
“The ones who really fight us are pregnant females, so we do not examine them. Every female gets an ultrasound while still in the water. If she is in her second or third trimester, she is immediately released.”
According to Dr. Greg Bossart, who holds the NOAA permit and oversees HERA research, Atlantic bottlenose dolphins are “charismatic megafuana” – which means they are fascinating to people – and McCulloch has to deal with a hoard of would-be participants each summer, selecting only those who can best contribute or most benefit from being part of the operation.
“We had scientists from as far away as Scotland and Australia this year,” he says. “We had four-time Space Shuttle astronaut Richard Linnehan on the team, representatives from marine parks and lots of students.”
McCulloch says observers from places like SeaWorld are important because they take knowledge gained back to their parks where they share it with millions of visitors, raising awareness of threats to ocean ecosystems and dolphin health.
He is especially proud of the program’s educational power.
“We had almost a dozen FAU pre-vet students, two FAU master’s students, two FAU post-docs, and 10 students from around the country who are part of MARVET. Gaining access to this type a marine mammal networking opportunity is invaluable for these students.”
MARVET is an acclaimed program at Mote Marine Laboratory in Sarasota that introduces veterinary students to marine mammal medicine. Goldstein participated in the program as a student and is now an instructor there.
“We have more than 40 scientists and institutions around the world collaborating with us,” says Bossart, a former Harbor Branch researcher who now heads the animal care and research programs at the Georgia Aquarium in Atlanta, the largest aquarium in the world and a center of marine mammal research.
Part of that collaboration involves analyzing samples taken in the lagoon each summer and creating new knowledge out of the data.
“It takes months to get results back from all the tests,” says Schafer. “The really exciting thing is new questions come up after each sampling. The coolest thing about HERA is it is constantly evolving based on what we saw the previous year to create a bigger picture of the ecology. It is like putting together a jigsaw puzzle.”
In the early years of the study, HERA researchers caught dolphins at random. Now, they often look for and examine specific dolphins to follow up on earlier observations. They want to see if diseases have progressed or gotten better, if an animal has new diseases or if its companions have caught an infection from it.
“Each dolphin has a unique fingerprint-like dorsal fin,” says Goldstein. “We have a catalogue of fin photographs and we can identify many individuals. We have an idea where they hang out, what locations they use to feed and survive, and we look for them and examine them.”
HERA operates year-round, with months of preparation beforehand as well as months of analysis afterward.
McCulloch says the tests conducted on each dolphins cost between $5,000 and $7,000. Overall the 10-day on-water operation costs around $200,000. The yearly cost of the program, including salaries and equipment maintenance and replacement, is approximately $400,000.
HERA is funded by the “Protect Wild Dolphins” license plate program, which McCullock helped create some years ago. Anyone who wants to support dolphin research can pay a little extra when they renew their car registration to buy one of the colorful plates that show a leaping dolphin against the backdrop of a Florida sunset.
“HERA could not exist without the money that comes from license-plate sales,” McCulloch says. “People can put them on their cars, trucks and boat trailers. There are gift certificates if you want to give one as a gift.”
The Harbor Branch program also receives some funding from NOAA.
“HERA began as a dolphin health study when I was at Harbor Branch,” says Bossart, who is still an adjunct faculty member at the institute. “It has evolved to look at ecosystem health and the health of humans. Because of their site fidelity, the dolphins provide a very good barometer of ecosystem health. They are like the canary in the coal mine.”
Site fidelity means lagoon dolphins born in the estuary live out their lives there, venturing into the open ocean only on rare occasions.
HERA researchers and other scientists have found that 50 percent of lagoon dolphins are ill and that they live on average only half as long as their free-ranging kin out in the relatively clean Atlantic.
“What we are seeing is not just concerning, it is alarming,” says McCulloch. “Nowhere else do you see this combination of known and unknown diseases, including viral, bacterial and fungal diseases and cancers.”
“What happens to them happens to us,” says world-renowned marine biologist Edie Wider, founder of ORCA – the Ocean Research and Conservation Association.