Sea Slugs are sometimes so colourful you can’t help but see them, but when you are looking for them, that can be a different matter! Nelson Bay in Port Stephens, just north of Newcastle, has long been known as a sea slug, or nudibranch, hot spot: so much so that there are now organised Sea Slug censuses to get a handle on the diversity of species, their numbers and seasonal occurrences.
The census is the brainchild of Dr Steve Smith from Southern Cross University’s National Marine Science Centre (NMSC) in Coffs Harbour who in a joint partnership with Underwater Volunteers NSW (UVNSW) and the Combined Hunter Underwater Group (CHUG), has organised 4 weekends so far over the past 12 months.
Volunteer divers from as far afield as Sydney, Muswellbrook and Coffs Harbour converged on Port Stephens on the 13th of September and had 24 hours in which to photograph and record every nudibranch spotted. The photographs are used by the organisers to verify sightings and to positively identify the species found. This time, a record 37participants in 18 teams, plus one intertidal searcher, surveyed 5 sites and identified 51 species. Given the small size and cryptic habit of nudibranchs generally, this was a great result and included 2 species thought to be new to the area which were sent away for expert identification. The highest number of species found was 15 species, by Kate Tinson and Cath Shorthouse.
The next census will be on 13th December 2014 and will be the first “Nelson Bay Nudi Festival” with organised events and talks. If you are interested in attending email seaslugcensus@gmail.com for more information. Five SURG members were in Port Stephens for the weekend enjoying ideal diving conditions: 8 or 9 metre visibility, 18 degree water and little wind. Photos of some of the nudibranchs and some of the group who took part in the census are shown here.