Scuba Season
Underwater at Hammerhead Point (Irizaki)
Scalloped hammerhead shark confirmed 3 months ago

Hammerhead Point (Irizaki)

Yonaguni · Japan

Open-water drift along the Kuroshio current off Cape Irizaki, the westernmost point of Japan, where scalloped hammerheads gather through winter — schools of 100 to 200 sharks are logged from January to March. There is no reef to hide behind: divers make a negative entry, drop fast and hover near 15–20 m in open blue water over a seabed close to 70 m, watching the current line for the massed sharks. Dive operator Kihachiro Aratake was scouting this hammerhead ground in 1986 when he came across the nearby Yonaguni Monument. Between shark passes the same current draws in dogtooth tuna, great barracuda and bigeye trevally, with the odd sailfish. Visibility often runs past 30 m, but winter north winds cut it back and regularly cancel boats.

Conditions

Depth

15 to 40 m

Advanced depths

Current

Can be moderate

Can pick up on the edge

Visibility

15 to 25 m

Clearest in the calm season

Water

21 to 29°C

3mm full or shorty

Month by month

MonthJanFebMarAprMayJunJulAugSepOctNovDec
Water (°C)212122232426272827252322
Vis (m)202020201515151515152020
CurrentStrongStrongStrongModerateModerateModerateModerateModerateStrongModerateStrongStrong

Your chances of seeing each animal

See all species recorded here →

Gear

  • Basic kit

    • Mask and fins
    • BCD and regulator
    • 5mm full wetsuit · cooler water
    • Dive computer