“When this shark came up on deck, it became very apparent almost immediately that there was a large wound on the back.” Bangley is a biologist at Dalhousie University. He studies sharks, so the injured blue shark he caught was in no danger — at least not from him. Chris Harvey-Clark says he estimates the shark that attacked the one they found was “between 4.0 and 4.4 meters in length” based on the bites. (Submitted by Chris Harvey-Clark) Bangley heads the Ocean Technology project at Dalhousie. He teaches marine biology students how to electronically tag sharks so their movements can be studied. But what he saw in this particular shark surprised him. “Once we laid it out over the side of the boat, where we take our measurements, things like length and girth and all that, we could actually see very clearly this big bite mark that was on the back of the shark.” The bite was fresh, maybe just a few hours old. Bangley asked his Dalhousie colleague Chris Harvey-Clark to examine the wound. Harvey-Clark is a marine biologist, shark expert and author of Maritime Marine Life. He knew what he was looking at. “It had absolutely classic great white shark bites on it.” Harvey-Clark was able to use the bite mark to estimate the size of the shark. “Somewhere between 4.0 and 4.4 meters in length. So it was a good-sized shark. You wouldn’t want to hit the shark on a dark night.” And Harvey-Clarke knows all about bumping into great white sharks. Last year, he was diving in the approaches to Halifax Harbor when he saw something very large swimming nearby. “Having a four-metre great white shark buzz repeatedly, you go in to check on you, you leave, you come back each time, you circle the shore, so if you were a seal your path is cut off. That’s a terrifying experience.”
Times are changing for great white sharks
Scary enough that Harvey-Clarke admitted he didn’t do as many dives this year as usual. He’s not afraid of great white sharks, but he has a healthy respect for one of the ocean’s top predators. And he thinks we’ll definitely see more of them in Nova Scotia waters. “We used to think that shark season was July to September. Well, shark season is now more like June to at least November. And that’s what surprised me when I met the shark last year. What’s a white shark doing here in November ? should be heading south by now.” No one really knows how many great white sharks are out there. They come here to feed on seals and there is no shortage of food. Harvey-Clark estimates there are about 440,000 seals in the Maritimes and they produce another 87,000 each year. This combination of abundant food and a warming ocean makes Nova Scotia’s waters more attractive to great whites and other shark species. Chris Harvey-Clark took this photo of a great white shark in Mexico several years ago. Because of the difficult conditions in Halifax, when he saw a similar animal last year, he had left his camera in the boat and did not capture a photo of the shark. (Chris Harvey-Clark) This is why shark tagging programs are so important. They expand our knowledge of where sharks live, feed and breed. And this is vital to understanding the health of not only sharks, but our oceans as well. This work is also being carried out by another Nova Scotia-based research group, the Center for Shark and Ray Conservation, led by another Dalhousie shark researcher, Manuel Dureuil. Compares the role of sharks in the ocean to wolves in Yellowstone National Park. When wolves returned to the park as top predators, they helped restore balance to a damaged ecosystem. “It’s similar in our oceans,” says Dureuil, “but we just don’t see it. We don’t see how degraded it is, and we never see the important role that sharks can play in stabilizing other populations.” One thing these shark researchers all share is their passion for these ancient animals—Harvey-Clark notes they’ve been in our oceans for 450 million years, “that’s longer than the trees have been around”—and the desire for more people to understand that sharks are not inherently dangerous, but a vital part of our underwater world.
Benefits of shark tagging for students
Manuel Dureiul says that when students participate in shark tagging, they have a unique opportunity to actually see the animals up close. “The shark looks at you and you see a big, predatory, beautiful animal. You’re not afraid of it. You’re just fascinated. It’s incredible. They’re such beautiful creatures.” They are also extremely durable. A blue shark attacked by a great white will likely recover very quickly from the experience. In 2014, the Department of Fisheries and Oceans estimated that 8,000 blue sharks are caught as bycatch in Canadian waters each year. (Nick Hawkins) “They heal from wounds like that and very, very quickly,” says Charles Bangley. “Well, I’d say by next year, you’d have a nice scar on that shark from that bite, but it wouldn’t be anywhere near those big open wounds.” Durable or not, the wounded shark was rejected for the tagging program. Electronic tags are surgically placed and are expensive. The researchers felt that this shark had been through enough. He was thrown back into the ocean. David Pate is a journalist, broadcaster and writer in Halifax. His latest project is the podcast “National Anthems: The Worst Songs in the World”.
