COMMENTS & OBSERVATIONS

The forecast showed four consecutive days of great weather/conditions however topside obligations and commitments threatened to derail any diving attempt but, …. I managed to make it out on the last of them, before the weather turned. The pick was dropped at the south-east corner of the island and 15 metre + visibility greeted my entry. Some of my bottom time was taken up with resolving equipment issues however, some sea slugs were still recorded. The swell was very low but had such a long period it created some surge above 10 metres. The most notable of those was our Goniobranchus sp. 04. This is a not-so-common species that seems to prefer a specific type of sponge. It has been proven to be a good species through the molecular sequencing work of Soong, Wilson & Reimer, 2020, separating it (identified as Goniobranchus sp. 4 in the paper) from many of those that also present with a red reticulation on the notum. It still has not been fully described and named though. The first dive saw an exceptional number of Goniobranchus splendidus recorded, more than the total of all the other species specimens combined.

[Soong, G. Y., Wilson, N. G. & Reimer, J. D. (2020). A species complex within the red-reticulate Gonio- branchus Pease, 1866 (Nudibranchia: Doridina: Chromodorididae). Marine Biodiversity 50: e25. https://doi.org/10.1007/s12526-020-01048-w]

Taxonomic Diversity:
Thirteen of the fourteen sighted species were nudibranchs, with 12 being dorids comprising 1 x phanerobranch (non-retractile gill), 4 x porostomes (suctorial feeders  of the Phyllidiidae family), 7 x cryptobranchs (retractable gill – all belonging to the Chromodorididae family) and 1 x cladobranch comprising 0 x aeolids, 1 x arminid and 0 x dendronotinids. A single head-shield slug completes the species count. If diet is considered then 13 of the 14 species sighted are spongivores.

Our Historical Data:
– This excursion brings the number of survey dives to 32 at this site since we commenced fully recording data here on 19/07/2010.
– 135 species have been recorded at this site.
– The most regularly recorded species at this site are: Goniobranchus splendidus (97%), Phyllidiella pustulosa (78%), Doriprismatica atromarginata (75%) and Phyllidia ocellata (72%). 
– Although not a lot of species were sighted this was an interesting dive nevertheless for what it turned up.
– This is the first time we have recorded Dermatobranchus ornatus or Goniobranchus sp. 04 at this site.
– The finding of Goniobranchus sp. 04 at this site is interesting. Although we have recorded it once off Coolum in July 2018, it is most often recorded by us on the reefs further south in the region off Currimundi where it is usually found on a particular species of finger sponge (refer to its Species Profile for an image of it on the sponge). However, we have not recorded the species since March 2019 and, on this most recent occasion, it was found crawling out on the substrate rather than on its “usual” sponge roost.
– Dermatobranchus ornatus, in the other hand, has been recorded by us fairly regularly throughout the Sunshine Coast and it is of interest that we have not recorded it at this site previously. One reason may be that on the second dive I moved out onto a sandy/gritty area with isolated rocks. Here there were a few colonies of the deep maroon-coloured gorgonian octocoral Astrogorgia sp. that we see them feeding on in our region. I have not seen this octocoral before at this site.
– The number of Goniobranchus splendidus specimens recorded continues to remain high at sites around the eastern edge of the island.
– This site last surveyed on 16/04/2023.
(Historical data courtesy of Terry Farr, who extracts it from his comprehensive database.)

Key to symbols
+++ New Species
+ First time sighted at this site
# Most commonly sighted at this site with %

TOTAL SPECIES SIGHTED: 14

DIVE IMAGES GALLERY

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