Udo Island Coral Field
Dive site
The tiny island of Udo off Jeju's east tip hosts a surprising subtropical coral field on its sheltered south flank — as far north as true scleractinian corals reliably grow in Korean waters. Dense colonies of brain and star coral alongside the kelp beds that typify Korean diving. The mix of tropical and boreal species in one dive is extraordinary and increasingly rare as climate shifts push ranges northward.
Conditions
Depth
5 to 22 m
Open water and up
Current
Usually gentle
Can pick up on the edge
Visibility
15 to 25 m
Clearest in the calm season
Water
11 to 27°C
5mm wetsuit
Month by month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Water (°C) | 12 | 11 | 12 | 14 | 17 | 20 | 23 | 24 | 23 | 19 | 15 | 12 |
| Vis (m) | 8 | 8 | 10 | 12 | 15 | 15 | 12 | 10 | 15 | 15 | 12 | 10 |
| Current | Gentle | Gentle | Gentle | Gentle | Gentle | Gentle | Moderate | Moderate | Gentle | Gentle | Gentle | Gentle |
Your chances of seeing each animal
Brain coral
Sometimes
About 1 in 3 dives
Korean sea anemone
Sometimes
About 1 in 3 dives
Korean rockfish
Sometimes
About 1 in 3 dives
Parrotfish
Rare
Now and then
Field journal
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