Specimens of world’s largest shark seen four times in six weeks off Eilat coast
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Specimens of world’s largest shark seen four times in six weeks off Eilat coast

Researchers map distinctive white spot patterns on backs of each whale shark for international database that will allow tracking

Sue Surkes is The Times of Israel's environment reporter.

A whale shark swimming in the Red Sea off the coast of Eilat, July 2019. (Shani Aloush, Israel Nature and Parks Authority)
A whale shark swimming in the Red Sea off the coast of Eilat, July 2019. (Shani Aloush, Israel Nature and Parks Authority)

Conservationists have spotted four members of the largest shark species on the planet off the coast of Eilat in the last six weeks.

Whale sharks, which are found in tropical seas all over the world, were not seen there at all last year.

Adi Barash, chairperson of Sharks in Israel and a doctoral candidate at Haifa University’s School of Marine Science, said it was hard to speculate about the reason. The group, which has been monitoring the presence of cartilaginous fish — primarily sharks and rays — off the Mediterranean coast for five years, is only in its second year of monitoring the Red Sea in Israel’s south.

Whale sharks, which are also the largest fish, are filter feeders, skimming plankton and small fish close to the surface and traveling great distances to find food. Their presence is seen as an indicator of healthy plankton populations.

Barash said the sightings needed to be matched with data on plankton collected by the Hebrew University’s Inter-University Institute for Marine Sciences in Eilat, which draws marine researchers from all over Israel.

Whale sharks, which can reach 15 meters (50 feet) in length, weigh up to 34 tons (68,000 pounds) and live for 80 years, are not dangerous to humans.

But they are an endangered species, primarily because of fin fishing, in which their fins are cut off for the Asian food industry and they are left to die.

While shark meat only fetches five to ten shekels per kilogram ($1.50 to $3), a pair of fins, used in the production of shark fin soup, can sell for $100, Barash said.

While fin fishing still goes on all over the world, conservationists in China have linked up with TV stars to campaign against shark fin soup and some couples are refusing to serve shark fin soup at weddings, all of which is raising awareness of the practice.

Whale sharks are also at risk of entanglement in fishing nets and of injury and death from passing ships, given that they feed so close to the ocean surface. Last year, a large vessel killed a whale shark in Jordan.

It is not known how many whale sharks exist in the world, as data can only be based on sightings.

Each whale shark has a unique pattern of white spots on its body.

A whale shark swimming in the Red Sea off the coast of Eilat, July 2019. (Shani Aloush, Israel Nature and Parks Authority)

Barash said the practice was to collect images of each shark, create a model of the spots and incorporate them into an international database so that each individual fish can be tracked through Jordan, Egypt, Saudi Arabia and even further afield.

National Geographic is currently running its two-week annual Sharkfest, a series of programming controversial among environmentalists for the way it can portray sharks as frightening.

“Sharks are endangered but not dangerous,” Barash said. “Four to ten people are killed each year by sharks, compared with 6,000 who are killed each year by lightning.”

The world’s second largest fish, the basking shark, also a filter feeder, has been spotted off Israel’s Mediterranean coast but not in the Red Sea.

Last year, a 20-meter (65-foot) blue whale was seen about 150 meters off the Red Sea coast. Israel’s Nature and Parks Authority said the sighting was especially rare because the whale was so far from its usual habitat in the far northern Atlantic or in the southern hemisphere.

The blue whale is the world’s largest mammal, and can reach up to 30 meters (98 feet) in length. The species was almost hunted to extinction in the first half of the 20th century, but conservation efforts have helped return some blue whale populations back to their pre-hunting numbers.

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