Looking like something out of the time of the dinosaurs, a huge fish that’s known as a basking shark was pulled up by fishermen off Australia this week, the first time the species has been caught there in 80 years.
The 20-foot (6.3-meter) long shark hails from the world’s second biggest fish species, behind whale sharks. It was caught accidentally by a trawler off Portland in southwestern Australia.
The shark is causing a sensation Down Under, where only three basking sharks have been reported in 160 years, according to Museum Victoria. The last one caught off the country was in the 1930s.
The sharks can grow up to 39 feet (12 meters) long and are known for their gentle nature.
The fish are called basking sharks (Cetorhinus maximus) because people occasionally see them at the surface, where they filter out tiny prey like copepods and shrimps for their dinners. But when prey is scarce at the surface they often dive deep, up to around 3,280 feet (1,000 meters), where they have been observed staying for months, based on satellite tags.
Not a lot is known about the distribution of the basking shark around the world, says Heidi Dewar, a biologist who studies the species with the National Oceanic and Atmospheric Administration (NOAA) in La Jolla, California.
“Typically we see them in more temperate waters,” she says, although they are thought to migrate long distances.
Basking sharks are accidentally caught semi-regularly by fishermen in New Zealand, although they seem to be most common in the North Atlantic, around the British Isles and the U.S. East Coast (see a picture of one that washed up on Long Island). They are also occasionally seen off the Pacific coast from California to Canada.
In warm tropical or sub-tropical waters they are rarely seen near the surface, most likely because they seem to avoid warm temperatures.
Hunted for Liver Oil and Soup
Basking sharks are listed as a “species of concern” by NOAA and as endangered in Canada, since their population seems to have declined over past decades. They are protected in waters of North America, the European Union, and a number of other places, but they are still targeted on the high seas and by illegal fishermen. That’s because their large fins are valuable for the shark fin soup trade.
Before the 1930s, basking sharks were regularly hunted in shallow water off the U.S. and Japan with harpoons, because their livers contained a large amount of valuable oil. But that market collapsed after cheaper alternatives became available from other sources.
Although basking sharks filter food like whale sharks, the two species aren’t that closely related. Sharks are an ancient line that has been plying the seas for 450 million years, since before the time of the dinosaurs.
“Basking sharks do look prehistoric,” says Dewar.