The Sea Slug Census is a collaborative citizen science program initiated by the National Marine Science Centre, Southern Cross University, and first delivered at Nelson Bay, NSW, Australia in December 2013 with the Combined Hunter Underwater Group.

Approximately 3,000 species of sea slug have been scientifically described across the globe, with estimates of at least the same number of species awaiting description and an unknown number awaiting discovery. Most sea slugs have rapid life cycles (<1 year) and are therefore highly likely to respond to changing environmental conditions. This suggests that they may have considerable potential for monitoring human-induced changes, including climate change.

Sea slugs are highly popular subjects for recreational, underwater photographers whose images consequently represent a potentially important record of patterns of species diversity and distribution. This Sea Slug Census project harnesses this enormous potential to document species distributions and to explore pathways for ongoing, volunteer-based biodiversity monitoring. The sampling framework allows the scientists to address key scientific questions whilst encouraging engagement amongst the participants to learn more about sea slugs.

Anyone can join the Vanuatu Sea Slug Census. Divers will have more chance of seeing lost of different species but many species of nudibranch and other sea slugs live in the shallows and you can find then in rock pools, in seagrass meadows and in the shallows. All you need is a camera and some enthusiasm! 

Next Event

2024 Sea Slug Census
11th to 19th May


Reports from previous years’ censuses can be found via these links:

Vanuatu Sea Slug Census 2021 Report

Vanuatu Sea Slug Census 2023 Report

35 species were observed during the  2023 Vanuatu Sea Slug Census

The 2023 SSC in Vanuatu took place just a month after 2 category 4 cyclones passed over the islands within 3 days of each other. There was also significant coral bleaching in the summer of 2022/2023. Nudibranchs were not as abundant as usual.

Some of the observations from the 2021 Vanuatu Sea Slug Census

2021 was the first time we undertook a Sea Slug Census in Vanuatu. Due to Covid restrictions there was no SSC in 2022