The type of plankton is broken down into warm water species in the Tushima Warm Current and cold water species in the Liman Cold Current, but the distribution of both types is not as clearly divided as water mass distribution and there is a wide sea area where they coexist.
種類は対馬暖流系の暖水種と、リマン寒流系の冷水種に分けられるが、両者の分布は水塊分布ほど明確に区分されず、混在海域が広い。