Swimmers beware! If ocean temperatures continue to rise, great white sharks could one day prowl B.C. waters.
To mark Discovery Channel’s popular Shark Week, which kicked off on Sunday, William Cheung, an associate professor at UBC’s Institute for Oceans and Fisheries, is speaking out on how, if it continues, climate change could bring new sharks never before seen in B.C. waters.
“With oceans warming, we do expect to see more tropical sharks in temperate waters,” Cheung said. “Based on my team’s computer simulation modelling, we found that climate change will cause an expansion of the range of great white shark to northern temperature areas, including the offshore waters of the northeast Pacific, which includes B.C.”
He said that you just need to look at the coast of California to see what could be coming to waters north of the border if we maintain the status quo and do not mitigate carbon emissions.
“Species in California include the oceanic whitetip shark, and the great white shark,” Cheung said. “In the Atlantic, we could expect to see great whites along the coast of Newfoundland. Currently, they have been recorded but sightings are rare.”
Ocean temperatures fluctuate from year to year; however, warmer waters are expected more frequently in the coming decades.
“During the warmer years, sightings of warm-water sharks, like great white, increase,” he said. “As the oceans warm, we expect to see sightings of these sharks more and more often.”
B.C. waters are no stranger to sharks. There are currently 14 species listed by the Department of Fisheries and Oceans. The most common are salmon shark, blue, Pacific sleeper, brown cat, spiny dogfish and tope (soupfin).
Cheung said that rising ocean temperatures will also shrink the populations of some species of sharks.
“Eventually, tropical waters will simply be too hot for the sharks to live in.”