Subtropical to cold-water,
in one country
한 나라에서, 아열대부터 한대까지.
Korea's underwater life is defined by the contrast between three distinct seas and two volcanic-island regions. Within a single country you can see everything from subtropical soft coral colonies (Jeju) to winter cold-water anemone beds (East Sea). The Tsushima Warm Current, a branch of the Kuroshio, drives the northward migration of subtropical fish.
Regional contrast is the framework
Directly in the path of the Tsushima Warm Current — soft coral colonies and subtropical fish year-round.
Steeply deepening and cold-water — cold-water fish and seaweed, winter fringed anemones, wreck-and-reef habitat.
Archipelago island diving — soft coral and seahorse habitat (Geomundo), reef and cobble-shore fish.
Offshore waters where cold and warm currents meet — the best visibility, sea fans and black coral, endangered corals and large migratory fish.
Where you see what
The signature subjects of each region — species details continue in the marine life encyclopedia.
- Jeju: Munseom soft coral, damselfish and subtropical fish; Beomseom large soft corals (up to ~2 m); Seopseom hard coral
- East Sea: Ayajin octopus and yellowtail; Wangdolcho a mix of cold-, warm- and open-water species (2006: 126 species); Ingu fringed anemones
- South Sea: Geomundo soft coral and seahorses; Yokjido rabbitfish, striped beakfish and octopus
- Ulleung & Dokdo: Jukdo sea fans, black coral and Asian sheepshead wrasse; Ssangjeongcho thousands of rockfish and yellowtail; Dokdo endangered corals
One country, the widest spectrum of life
From subtropical soft coral to cold-water anemones — few places let you see such a wide underwater spectrum within one country. The encyclopedia covers 21 species of coral, fish, invertebrates and marine mammals.
- The West Sea is mudflat-based with low visibility and strong currents, so most diving-life data is pending.
- Regional species descriptions are a mix of ✅/🟡 — see the notes for each species and site.