Jul 1, 2021

Basking Shark

Many a maritime sea-monster tale has originated from sightings of our next featured shark species. So sit back and 'Bask' in the glory of this gentle giant!

Time to get to know this huge yet lesser-known shark species - the Basking Shark. But don't get too close, contact with its rough skin have been known to inflict damage on divers and scientists alike.

FAMILY: Cetorhinidae

SCIENTIFIC NAME: Cetorhinus maximus

COMMON NAME: Basking Shark

It's name comes from its habit of ‘sunning’ itself at the water's surface.

TYPE: Fish

IUCN Red List Status: Endangered

SIZE: Basking Sharks are the second largest shark species and are extremely slow-growers. This species can reach an impressive 40 feet(~12m) length, with average adults measuring around 22-29 feet (6-9m) and weighing in at over 5 tons!

More studies are needed to learn the mysterious life behind Basking sharks but it is believed that these sharks grow to 16-20 feet (5-6 m) or reach an average age of 18 years before sexually maturing, with a gestation period of 3 years or longer.

AVERAGE LIFE SPAN:

The maximum lifespan of the Basking Shark is estimated at 50 years

DISTRIBUTION: Basking sharks are a highly migratory, coastal-pelagic shark that's found throughout the world’s arctic and temperate waters.

Basking sharks are always on the move, following the high zooplankton (their main food source) density that blooms in various areas seasonally.

Sightings suggest that male and female basking sharks live at different places and only come together for mating events; they are also known to enter bays and estuaries along their migration routes.

DID YOU KNOW:

Basking sharks are often seen traveling in pairs and in larger schools of up to a 100 or more!

DIET: One of three filter-feeding shark species, the Basking Shark is the only one that relies solely on the passive flow of water through its pharynx by swimming.

Most often sighted swimming close to the surface with their huge mouths open, they filter about 2,000 tons of seawater per hour, using their gills to scoop up zooplankton. As these gentle giants move through the water feeding, they often twist their bodies performing a full 360° roll.

Watch Them in Action:

VIDEO VIA BBC Northern Ireland

CONSERVATION: Although Basking sharks are one of the most protected shark species, they are hunted for their oil, meat, fins, and vitamin rich livers. In fact, the Basking shark's liver accounts for 25% of its body weight! Since their liver is high in squalene, it helps give the shark near-neutral buoyancy.

Unfortunately, fishing in China and Japan still drives the demand for their fins which are sold for shark fin soup. Their livers are also sold in Japan as an aphrodisiac, a health food, and its oil as a lubricant for cosmetics (read more about squalene here). These huge sharks are also victims of commercial fishing impacts, pollution, by catch, poor regulation and other human-caused oceanic threats.

DID YOU KNOW:

People have witnessed individual Basking Sharks leaping from the water or rubbing themselves against rocky coastline! Although this behavior is not fully understood, it's believed the sharks may be trying to rid themselves of parasites or commensals like remoras or sea lampreys (Petramyzon marinus), which are often seen attached to their tough skin.