Tiger Sharks Are Moving North As Climate Change Takes Hold

The warming of the oceans as a result of climate change is altering tiger sharks' migratory behavior and could push the predators into conflict with humans, a new study has warned.

The paper, which was published in the journal Global Change Biology, showed that tiger sharks are increasingly being found further north.

Tiger sharks are a key apex predator in their typical habitats and help to regulate finely balanced eco-systems. The findings suggested that changes to where they migrate could result in knock-on effects for other species, as well as humans.

As one passage from the paper, which was co-authored by Dr. Neil Hammershlag of the Rosenstiel School of Marine and Atmospheric Science at the University of Miami, read: "Climate-driven alteration to the movements of large predators, such as sharks, could change their likelihood of encounters with recreational water users (Chapman & McPhee, 2016) and/or cause altering ecosystem dynamics through novel trophic cascades..."

Trophic cascades occur with the addition or removal of key predators into an ecosystem, causing knock-on effects for the other species. The paper warned that this could occur as a result of ocean warming in relation to tiger sharks and where they are found.

The sharks themselves though are not particularly picky when it comes to their interactions with prey.

"I am not surprised we found these patterns, but surprised how strong the patterns are," Hammershlag told Newsweek. "Tiger sharks have no natural predators and can feed on almost anything, so their movements are not restricted by predators or prey, so they can just follow their optimal temperatures," he said.

As the study's conclusion stated, with ocean warming, tiger sharks could follow those optimal temperatures and move into zones where conflict between humans and animals becomes more likely.

"Given their role as apex predators in tropical and subtropical seas... climate-driven changes in tiger shark space use and migratory patterns could lead to shifts in ecological interactions through alterations in predator-prey dynamics, and may also redistribute sharks into areas where human-wildlife conflict is likely to occur," one passage from the study's conclusion reads.

Tiger sharks bear distinctive striped patterns that give them their name. They have a dangerous reputation as powerful predators.

Large tiger sharks can grow up to 20 feet in length and weigh almost 2,000 pounds. Tiger sharks, great white sharks and bull sharks are the shark species most likely to attack humans.

"Personally, they are my favorite shark and I love nothing more than diving with them, taking photos of these magnificent animals," Hammershlag said. "That said, they are apex predators and deserve that respect. While they are not out to get humans, they are also not domesticated animals. They are predators.

"Tiger sharks are one of the few species of sharks that pose real danger to human swimmers, divers and surfers. While a tiger shark bite is rare, they do inhabit coastal waters and since they are so large and strong, a bite can be fatal, even if a relatively minor investigatory bite," he added.

Tiger shark in French Polynesia
A tiger shark seen in French Polynesia. The study showed that the animals migratory habits were moving further away from the equator and towards the poles amid ocean warming. Alexis Rosenfeld / Contributor/Getty Images