COMMENTS & OBSERVATIONS

A busy mid-week morning at the La Balsa Park boat ramp. Just after dawn found Li’l Mischief anchored at the Trench dive site. The anchor lay in 18 m of water so I checked its position and then started to head up the drop off to search the plateau in 14 m of water in order to extend my bottom time. On the way up I noticed a very small speck of yellow on the substrate which turned out to be a 5 mm specimen of a new species of Verconia for our list (Verconia sp. 06 = Verconia sp. 5 of NSSI-ii). It presented with a single rhinophore that appeared to be the result of a developmental error rather than a predator’s attack. Roughly equal species numbers sighted on each dive. Ardeadoris egretta was a nice find, and very photogenic too, being recorded at this site over the past couple of months, but I was fortunate to come across two specimens. The number of Chromodoris elisabethina specimens is staying high in comparison to other species at this site.

Taxonomic Diversity:
22 of the 23 species sighted were nudibranchs, with 17 being dorids comprising 2 x phanerobranch (non-retractile gill), 4 x porostome (suctorial feeders – all of the Phyllidiidae family), 11 x cryptobranchs (retractable gill – all except one belonging to the Chromodorididae family) and 3 x cladobranchs comprising 3 x aeolids, 1 x arminid and 1 x dendronotinid. A single sacoglossan rounds out the species numbers. If diet is considered then 15 of the 23 species sighted are spongivores.

Our Historical Data:
– This excursion brings the number of survey dives to 38 at this site since we commenced fully recording data here on 10/07/2010.
– 134 species have been recorded at this site.
– The most regularly recorded species at this site are: Doriprismatica atromarginata (97%), Phyllidiella pustulosa (95%), Thuridilla cf. splendens (82%) and Chromodoris elisabethina (79%).
– This is the first time we have recorded Verconia sp. 06 on the Sunshine Coast.
– This is the first time we have recorded Ardeadoris egretta or Cratena lineata at this site and only the second time we have recorded Goniobranchus albonares or Gymnodoris alba  here.
– The bar graphs show a possible seasonal pattern to the seasonal abundance of Doriprismatica atromarginata and Goniobranchus splendidus at this site. (See Image Gallery below)
– This site last surveyed on 29/01/2023.
(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: 23

DIVE IMAGES GALLERY

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