Nate Rouette and his brother Nelson headed out shark fishing on Cape Cod hoping for an exciting catch. What they reeled in shocked them: a tropical tiger shark known for eating almost anything it can swallow.
The brothers, longtime sport fishermen from Massachusetts, released a juvenile tiger shark in late July after catching it from a beach in Falmouth, Massachusetts. The 5-foot shark typically inhabits warmer, southern waters such as the Caribbean Sea, and scientists said its arrival off New England signals warming seas driven by climate change.
Nate and Nelson said the late-night catch came after hours of pursuing more common brown sharks.
“And I saw those horizontal lines, indicating it was a tiger shark, which was super cool,” said Nate, who is the social media manager for On The Water magazine. “Immediately I started yelling to my brother, ‘It’s a tiger, it’s a tiger shark!’ And he was in disbelief.”
About tiger sharks
The brothers caught a young specimen of a species that can reach more than 15 feet (4.6 meters) and 1,400 pounds (635 kilograms). Tiger sharks eat a wide variety of ocean life , fish, crustaceans and birds , and are infamous for sometimes swallowing man-made items such as old license plates and shoes that show up later in their stomachs. Adults are more dangerous to humans than most shark species, though unprovoked fatal bites are rare.
What scientists say
John Chisholm, an adjunct scientist at the New England Aquarium’s Anderson Cabot Center for Ocean Life in Boston, said juvenile tiger sharks have shown up more often in northern waters in recent years. Rising sea temperatures appear to have made the Atlantic off New England more welcoming to them, he said.
Young tiger sharks have historically been less common than adults in northern waters, making the brothers’ discovery especially surprising, Chisholm said.
“Maybe they are coming up here because conditions are right. There’s food, there’s warm waters,” he said. “Maybe it’s becoming a nursery , that’s one of the issues that we will investigate.”
Other species moving north
Tiger sharks are among many species of sea life trending north as oceans warm, and other sharks have followed suit, scientists have said. Great white sightings off Cape Cod have become increasingly frequent, and the large predators have also appeared off New Hampshire and Maine. Scientists have linked the rise in great white sightings to factors including a growing seal population, the sharks’ primary prey in the region.
Other animals, including black sea bass, also appear to be shifting north as the ocean warms.
For the Rouette brothers, the encounter with a tiger shark provided a thrill they won’t forget. Nate said the discovery was a reminder of that warming.
“People are definitely seeing more species that indicate that,” Nate said.