More than 14,000 valid copepod species are known, about half of which live in symbiotic associations with nearly every animal group, ranging from sponges to chordates. Copepods are common parasites of marine and freshwater fishes and are known to cause diseases in finfish and shellfish aquaculture. They may also serve as useful bioindicators of host dispersal, host phylogeny, host population structure and both natural and anthropogenic disturbances. Only about 2% of aquatic invertebrate species and less than 20% of fishes have been surveyed for symbiotic copepods, which means there are many more symbiotic copepods waiting to be discovered and formally described.

The global shortage of technical expertise in copepod taxonomy is a threat to biodiversity studies and aquatic animal health industries. The 4th International Workshop on Symbiotic Copepoda (IWOSC) aims to combat these issues by offering training opportunities to copepodologists and parasitologists.

This workshop comprises an 8-day, fully residential event including research presentations, laboratory based workshops and the opportunity for participants to help collect workshop-related specimens in the White Sea. Moreover, in the spirit of the 2nd and 3rd IWOSC which included a 1-day Branchiura and parasitic Isopoda workshop, respectively, the 4th IWOSC will dedicate one day to the Tantulocarida.