Diving Kanto’s Coast

Divers in Tokyo will undoubtedly be thrilled to discover a colorful underwater world lies just beneath their doorstep. Bonnie Waycott travels to nearby Atami and Miyagawa Bay and finds you don’t have to go far from the capital to enjoy some great diving.

When it comes to scuba diving in Japan, Okinawa and Japan’s southern prefectures undoubtedly spring to mind. Their crystal clear warm waters and exquisite beaches are deservingly summer hot spots. But areas near Tokyo can be just as beautiful for underwater exploration.

In fact, some of the best diving can be found within easy reach, just south of the capital in Shizuoka and Kanagawa prefectures. With a mix of tropical and cold-water fish, north- and south-flowing currents, rocky shores, well-preserved coral and shipwreck exploration, there’s an exciting range of opportunities for divers of all levels.

Amazing Atami

Built on a volcanic caldera, Atami, which literally means “hot sea,” has been famous for its hot springs since the 8th Century. In 1950, the city was declared an International Tourism and Culture City by the Japanese government, and when it became a stop on the Tokaido Shinkansen Line, its popularity soared. Today it draws thousands of holiday makers, especially in summer.

Most of Atami’s dive sites are on the west end of a bay, about five-to-10 minutes by boat from the mainland. Famous for rocky outcrops and a large shipwreck suitable for advanced divers, Atami’s dive sites are calm and accessible, offering an array of marine life from soft coral and sponges to macro life and schools of fish. Moray eels lurk in dark corners, while more observant divers may spot colorful nudibranch or a well-camouflaged stonefish.

Lust for Rust

One of Atami’s most frequented dive sites is the Chinsen, a ship that lies in two sections at around 25 to 30 meters. Due to its depth, and a mild current that can sometimes occur at the surface, it’s only accessible to divers with an advanced certification.

The dive begins off a boat and down a long rope with nothing to see until the wreck comes into view around 21 meters. The top of the structure is a wondrous dive in its own right. Schools of anthias, cardinals and chromis move about, while stonefish and moray eels rest in the darker corners.

Orange anthias and patches of small anemones can be seen toward the sides of the wreck, impressive when viewed from above, but mesmerizing when right in front of your eyes. Deeper down at around 28 meters, dense growths of soft coral seem to form artistic mazes over the wreck, creating the perfect sanctuary for fish at the first sign of danger.

Meanwhile, fan-like species drape from opportune edges, spreading wide into the water. Damselfish and sea goldies patrol the area, and schools of fish swarm down into the deep. The dive starts with the hull and front area and is easy to navigate — follow the sides until you reach the back of the section, then swim past the rest of the structure which eventually takes you back to the starting point. Divers with good air consumption can explore both sections of the wreck in one dive.

The Beauty of Bitagane

Next to the Chinsen is Bitagane. Here, fields of sponges, soft corals and a scattering of anemones are a haven for species such as yellowstripe butterfish and cherry anthias. This site is packed with diverse marine life and has an abundance of coral.

Huge rocky structures sprout from the deeper areas, full of soft corals and multitudes of fish, especially various species of sea goldies, the odd seven-band grouper and a medium-sized flatfish or two resting quietly among the colorful scene.

The shallower areas are well-stocked with smaller critters such as the nudibranch in bright red and yellow. Black scrapers hover in the blue, while growth is impressive and healthy as a variety of corals and sponges carpet the tops and sides of the rocks like a vast flowerbed.

Finning over the rocky structures, sea urchins and small shellfish seem to be everywhere, and a couple of stonefish appeared to give me a sideways glance as I passed slowly by. Swimming down to the sloping rocky walls, at depth there are more sponges, gorgonians and schools fish, while the odd crinoids bring a smile.

Miyagawa Bay

Miura Peninsula in southeastern Kanagawa protrudes into the sea between Tokyo Bay and Sagami Bay. The area is famous for a western-style lighthouse that watches over ships as they arrive and depart, while the bustling Misaki Harbor, famous for tuna fishing, is a great place to eat fish fresh off the boats.

The vast waters off Miyagawa Bay are home to some fascinating biodiversity with clusters of rocky structures, outcrops and boulders. Just 75 minutes from Tokyo’s Shinagawa Station, it is home to a series of rock formations, soft coral and some impressive macrolife.

Mythical Macros

Miyagawa Bay’s underwater pinnacles are full of action and color, with visibility around 10 to 15 meters and some lavish marine life, although pelagics are few. As the descent begins, the water features some rock formations, pinnacles and ridges crested by soft corals.

One of the attractions is a distinctive rocky structure with overhangs. Resident eels rest in the darker areas, sometimes with cleaner shrimp companions, while nudibranchs can be found at all depths, and various anemones are on display too.

At first glance, some areas appear to be almost devoid of life, but here photographers will want a macro lens and a light handy, as this area is home to sponges that rise here and there, rocks adorned with frills of soft coral and crinoids that make full use of the nutrient rich waters flowing past.

Fish, such as the half-lined cardinal fish are photogenic, but swim closer to the rocks and deeper toward the sandy bottom and more discoveries await. Small crabs roam around here and there, and nudibranchs live on the surface of the rocks in partnership with colorful anemones.

After exploring the rocks for a while, I found a resident eel that looked up and hid at the very back of its den as I swam past. The maximum depths at Miyagawa Bay are around 20 meters, and the rocky walls fall down onto a sandy seafloor.

Other areas further along are also home to impressive coral growth including gorgonians, whip coral and fans as well as more abundant marine life and a swim-through tunnel covered with substantial growth.

Moray eels are seen in the deeper areas as well, and can be quite tolerant of divers. Black-sided pipefish hover in the tiny rocky cracks, shrimp team up with sea urchins and keep an eye on divers swimming by, and hunting lionfish make regular appearances.

However, the best surprises are kept for the shallower areas at around 10 to 20 meters as these are jam-packed full of life. Macrolife fans will be drawn in by seahorses, nudibranchs and frogfish. Red soft coral makes for seductive color patches that lure sea goldies and other schools of fish, but the star of the show is undoubtedly the tiny harlequin shrimp; its white and blue colors lighting up against divers’ torch lights under the protection of a small cave-like opening.

Sometimes there are fairly strong currents in Miyagawa Bay, but this brings with it rich nutrients from the deep sea floor and gives the area a good diversity and quantity of marine life. The rocky structures are habitats for damselfish, parrot fish, yellow chromis and banded coral shrimps that light the wall with their vivid colors.

A few starfish and sea slugs are also present. Looking up at the impressive rocky structures rising into the blue is a nice final touch during the ascent back to the surface.

Whether you’re a keen photographer, a shipwreck fan or just want to relax and observe the marine life, there’s something for everyone at Atami and Miyagawa Bay. With leisurely day-trip dives and plenty of photo opportunities, these places won’t disappoint.

PRACTICALITIES

GETTING THERE

To Atami, take the Tokaido Shinkansen Kodama from Tokyo’s Shinagawa Station. The journey takes about 45 minutes and costs just over ¥3,500 for a single unreserved seat. The cheaper route is the JR Tokaido Line, which takes two hours, for about ¥1,900. To Miyagawa Bay, take the Keikyu Line from Shinagawa Station to Misakiguchi Station. It takes about 75 minutes and is a bit less than ¥1,000.

GETTING AROUND

Hiring a car is a good option to explore the area if you have a few days to spare; otherwise the dive shops offer pick-ups and drop- offs for day trippers.

WHEN TO GO

June to September are the warmest months when temperatures reach between 20°C and higher than 30°C in mid-summer. December, January and February have the lowest temperatures at around 6-9°C.

WATER TEMPERATURE

Varies between 18-27°C in July and August to around 23-26°C in September and 18-24°C in October. A 5-mm. wetsuit will suffice during the summer, but a dry suit works well from October and later.

DIVING TOURS AND TIPS

Check out Discovery Divers Tokyo for further information on summer trips to Atami. DTT offers recreational, leadership and technical courses, as well as monthly socials in Tokyo and fun dives in the Izu area in summer.

For trips to Miyagawa Bay, Hayama-based Nana Diving is a great place to start. Depending on weather conditions, they offer dive trips to Zushi and Hayama as well as Miyagawa Bay.

Note they don’t speak much English and can only answer basic English e-mail inquiries. If you don’t speak Japanese and want to dive off Hayama and Miyagawa Bay, feel free to e-mail bonniewaycott@gmail.com or visit my Facebook page, Rising Bubbles.