Features
Of Fish and Folly
Biologist's work with fish and other marine creatures — and the occasional misstep — to be focus of lecture
BY ANDREW VOWLES
He'd had painful encounters with a few nasty aquatic critters before, but nothing came close to the stabbing Prof. Jim Ballantyne, Integrative Biology, endured a few years ago on the northern portion of Australia's Great Barrier Reef. It didn't help that the incident occurred before the eyes of a class of horrified U of G students.
It happened during a tropical field course run by Guelph at the Australian Museum's Lizard Island Research Station. Ballantyne had been wading just off the beach to see what creatures had been netted. He figured anything swimming freely — including any stingrays — would have fled at his approach.
It was a blue-spotted lagoon ray. That much he absorbed before the creature lashed its whip-like tail, flicking a razor-sharp barb through his rubber boot and into the top of his right foot. After that, he had little mind for anything but enduring the agony induced by the venom.
“It was the most painful thing I've gone through,” says Ballantyne.
For the next eight hours, no amount of painkiller had any effect. Fortunately, he says, the finger-length barb had penetrated only half an inch into his foot and had come back out. The next day he was hobbling but back in front of the class.
Today he grins as he recalls the less-than-stellar moment. It's one of a few hard-learned lessons he's absorbed in tropical parts of the world while pursuing his studies of the physiology of aquatic organisms. Ballantyne will discuss his recent investigations of elasmobranchs — a group of fishes, including rays, skates and sharks, whose skeletons are made of cartilage rather than bone — during a public lecture this week on campus.
Until recently, the longtime Guelph faculty member focused on metabolic and genetic studies of bony fish species, including Arctic char. That meant he studied creatures found about as far from the Great Barrier Reef as he could get — and spent more time diving in frigid northern waters than wading in tropical lagoons.
His interest piqued about six years ago by reports of stingrays living in rivers of Malaysia, Indonesia and Thailand, he began looking into the biology of these creatures.
In their watery world, fish and other organisms need to find ways to keep the correct amounts of water and salts in their bodies. Species living in salt water have lots of urea in their tissues to maintain osmotic balance. Their freshwater cousins, whose ancestors are believed to have left the seas for new homes in fresh water, need to make little urea.
Ballantyne is particularly interested in how the metabolic workings of marine and freshwater types have adapted to keep their nitrogen balanced in varied environs. He's found that some freshwater species are able to alter their internal chemistry to live in dilute salt water. Others are less adaptable.
He's also learning about the genetic relatedness of species of Himantura in Southeast Asia and how they differ from freshwater stingrays in other parts of the world, mainly South America. Although he stresses that he's not a conservation biologist, he says learning more about these creatures may help in efforts to preserve endangered species.
Scientists know little about how freshwater stingrays live, says the Guelph biologist, whose work is already making him one of only a few experts worldwide.
During his lecture, Ballantyne will discuss his field trips to Southeast Asia in search of study specimens. His travels so far have taken him to fish farms and wet markets, where he's seen stingrays ranging from the size of dinner plates to wingspans wider than his outstretched arms.
His talk will also lay bare a few revelations about his own faux pas during research and teaching trips abroad. Once he was wading through a shallow tank at a fisheries research station in Thailand with a stingray whose tail spine had been removed — or so he'd been led to believe. There'd been some kind of “translation problem,” as he puts it, recalling the creature's whip-like appendage.
That time, he was more fortunate than on the Lizard Island beach. “I've been stabbed by all kinds of things — urchins, fire worms, fire coral,” he says.
Ballantyne got lucky again while snorkelling one day off the coast of Australia at Perth. He'd grabbed a few shells from the ocean bottom but had nowhere to carry them, so he'd tucked them inside his bathing suit. Only after he'd spread out his collection on the beach did he notice the tiny creature nestled inside one of the shells: a poisonous blue-ringed octopus.
“I had it in my Speedo, where it could have done maximum damage. I don't put shells in my Speedo anymore.”
Here in Guelph, he's equipping space in the Hagen Aqualab to study coral and giant clams. Coral such as that found on the Great Barrier Reef is laid down by invertebrates living in partnership with food-providing algae. The same kind of symbiosis allows giant clams to acquire food, especially nitrogen, in tropical waters that are typically low in the nutrient.
He'll use new equipment and stable isotopes in the lab to map how nitrogen moves between algae and clam tissues. Along with PhD student Jake Robinson, Ballantyne also plans to investigate possible biomedical applications that may prove useful in tackling human metabolic diseases.
Ballantyne will speak on “Death, Where Is Thy Stingray? Silly Things I Have Done in the Interest of Science” Feb. 2 at 12:30 p.m. in Room 168 of the Axelrod Building.