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Honshu's Must-do Shark Dives

HONSHU’S MUST-DO SHARK DIVES

FEATURE AND PHOTOGRAPHY ANDY MURCH – BIG FISH EXPEDITIONS

 Japanese horn sharks are quite common on the reefs near Shark City.

Japanese horn sharks are quite common on the reefs near Shark City.

When one thinks of Japan, world-class shark diving may not be the first thing that comes to mind, but beyond Japan’s cultural allure, lies a vibrant marine ecosystem, patrolled by a fascinating assortment of endemic sharks.

The Japanese archipelago stretches from chilly Hokkaido Island in the northeast, to tropical Yonaguni Island in the southwest. Dominating the centre of the chain lies Honshu Island; Japan’s largest landmass.

In the summer, Honshu basks in the warmth of the Philippines’ current, but in the winter, icy cold water pushes down from Russia, lowering temperatures by a whopping 30ºC. Honshu’s fish species have evolved to tolerate the extreme temperature fluctuations, so it is not unusual to see endemic butterfly fishes swimming next to rockfish that one would expect to find in the arctic. Not surprisingly, Honshu’s sharks and rays are just as diverse. Many are found nowhere else on the planet.

Beautifully patterned banded houndsharks can be seen at no other location.

Beautifully patterned banded houndsharks can be seen at no other location.

Star-spotted smoothhound shark.

Star-spotted smoothhound shark.

Although endemic sharks can be seen virtually anywhere around Honshu Island, there are a couple of locations that should not be missed by visiting shark fans. At a dive spot called ‘Shark City’ near Tateyama in southern Chiba, hundreds of banded houndsharks gather each day to enjoy a free lunch, compliments of Bommie Dive Centre. Banded houndsharks are a locally common but extremely elusive species that is virtually impossible to encounter elsewhere. The sharks are roughly a metre long, greyish-tan above, pearlescent below, and beautifully patterned with small black flecks, scattered over subtle dusky saddles.

The houndshark feed takes place in 20 m of water, just a few minutes boat ride from shore. Before the dive, participants receive a thorough briefing by dive shop owner Kan Shiota; a friendly, English speaking dive instructor, and the visionary who turned a regular reef diving spot into a bucket-list destination for shark lovers.

Upon descending, divers are immediately greeted by a layer of sharks, milling around on the dark volcanic sand while they await the arrival of the shark feeder.

Kan brings down a basket of frozen fish, which he tethers to a rock. As if on queue, the closest sharks switch gears and bolt towards him. Unfazed by their enthusiasm, he cracks open the crate and offers a handful of fish to the nearest pint-sized predators. As he doles out his fishy treats, more sharks arrive, wriggling and tumbling over each other in an effort to consume their share. There are so many sharks that Kan sometimes disappears in the centre of the swarm. Clearly not claustrophobic, he continues to guard the bait crate, even though at times there are more sharks than water.

Tateyama’s reefs are covered in vibrant soft corals.

Tateyama’s reefs are covered in vibrant soft corals.

Eventually Kan rises theatrically out of the centre of the maelstrom, leading the swirling mass of sharks upwards as he does so. The result is an enormous twister of sharks that looks like a scene from the movie ‘Sharknado’.

Among the houndsharks, visiting divers can also see hundreds of red stingrays; another species endemic to this part of the world. The rays are just as eager as the sharks; pushing their way into the centre of the feed.

By the end of the feed there are more sharks than water!

By the end of the feed there are more sharks than water!

The spectacle usually lasts around 30 minutes. While it unfolds, divers have plenty of opportunities to take hundreds of images or simply to look on entranced, until their dive computers force them back to the surface.

Intricately patterned Japanese butterfly rays can be found in the sand on many of Honshu’s dive sites.

Although Shark City is a commercial enterprise, it also has an important environmental value. Before Kan arrived, the banded houndsharks were a nuisance to local fishermen, causing damage to their nets. To avoid losing their catch, the fishermen were sometimes forced to kill the sharks, so Kan wanted to see if he could draw the sharks away from danger by feeding them.

Unfortunately, the banded houndsharks turned out to be as timid as they were beautiful. They would not come anywhere near him, even if he carried bait. Unperturbed, he tried leaving the bait on the seafloor and returning to the boat until they had consumed it. That seemed to work, so he repeated the process over and over, until the houndsharks finally got used to him being in the water with them.

Eventually, they got used to groups of divers too, but it took five long years for Kan to completely habituate them. Now, Shark City attracts hundreds of houndsharks every day and is a big hit with local divers.

Blotchy swellsharks are rarely seen by divers. Japanese wobbegong sharks are masters of camouflage.

Banded houndsharks are not the only cartilaginous predators to call Tateyama home. If you get tired of Shark City, the adjacent reef is a great place to search for Japanese horn sharks; a beautiful endemic species with zebralike vertical stripes and two large dorsal fins equipped with menacing-looking fin spines.

Unlike their banded cousins, horn sharks are bottom dwellers that hide within crevices in the reef. Once located, they generally stay put, allowing divers to get a very close look at them.

While exploring the reef structure, it is also a good idea to keep one eye on the sand, where endemic Japanese angel sharks and exquisitely patterned Japanese butterfly rays can sometimes be seen hiding in plain site.

Chiba’s Shark City is a year-round destination, but it is best to visit some of southern Honshu’s shark diving spots ‘in-season’. For example, during September and October, schooling scalloped hammerheads congregate around tiny Mikomoto Island at the southern tip of the Izu Peninsula.

Touted as Japan’s mini-Galapagos, Mikomoto is an exposed, barren islet, topped by a forlorn looking lighthouse. What it lacks in terrestrial charm, Mikomoto makes up for in big animal activity. Its remoteness, relatively strong currents, and proximity to deep water make it a magnet for pelagic sharks, including hammerheads, grey reef sharks and oceanic blacktips.

If you’ve already ticked those sharks off of your life-list, then you may prefer to visit Mikomoto during the winter months when Japanese angelsharks and cloudy angelsharks are in residence.

Bommie Dive Centre owner Kan Shiota is the visionary that created Shark City.

Another of Japan’s endemic shark species that visits Mikomoto is the Japanese Wobbegong Shark. It is strange to find a wobbegong this far north because all other members of the family live in the southern hemisphere, but local divers that are prepared to brave Honshu’s winter temperatures, often see dozens of these odd looking sharks lounging on Mikomoto’s colourful reefs.

Cryptically patterned and adorned with facial skin flaps that obscure their mouths, Japanese wobbegong sharks are masters of camouflage and expert ambush predators. They are capable of remaining motionless for many hours, blending into the reefscape until an unsuspecting small fish swims within striking distance of their powerful jaws. Then, they lunge forward, mouth agape and clamp down on their victims with needle-sharp, snake-like fangs. There is no escape from the jaws of a Japanese wobbegong!

The Japanese angelshark.

If you’re extremely lucky, Honshu has even more endemic shark species that you could run into, such as the blotchy swellshark and starspotted smoothhound. Your chances of finding those two are pretty slim unless you dive year round but you never know. Either way, there are enough exotic predators in Honshu to keep even the most jaded shark diver entertained.

LOGISTICS

Tateyama and Mikomoto are both within driving distance of Tokyo. Getting there on public transport can be a challenge for foreigners, but it is possible to rent a car installed with an English language GPS.

Or, you can join a trip with Big Fish Expeditions who run yearly ‘shark safaris’ to dive with all of Honshu’s endemic species.

Large schools of scalloped hammerhead sharks can be found at Mikomoto Island during September and October each year.

Email: info@bigfishexpeditions.com www.bigfishexpeditions.com