Julie, Terry and David on this excursion consisting of 1 x 70 minute and 1 x 73 minute dives in water depths of 14 m to 20 m. 12 m viz, 20 C water temp and no surge.
As better conditions return to the Sunshine Coast so we are seeing an increase in the
diversity and populations of the sea slugs. Dropoff is a site we have only dived twice before. There is a large "bluff" at the north-west corner of the plateau in this section of reef. We don't think we were right on the mark this time but the various terraces still held plenty of interesting growth and critters. They seemed to improve in variety and coverage the shallower we went which also meant we were moving away from the sandy substrate along the edge at the deepest part. The proximity of the sand there would affect sessile growth through smothering and abrasion in times of surge.
Take a moment to compare the differences between two specimens of Flabellina rubrolineata in the images below. Also compare the two different juvenile specimens of Hypselodoris jacksoni. Although both are the same size, one (in situ image) has all the features that allow us to recognise it as such whereas the other (microscope image) lacks the orange mantle margin, has a plain tail and exhibits a blue crescent anteriorly that has never been present in any specimens we have observed before, either juvenile or adult.
Number of each species sighted: 1st dive/2nd dive
* Species with highest specimen count
Ardeadoris aff. averni -/3
Cadlinella ornatissima 1/-
Chromodoris striatella 1/-
Dermatobranchus cf. primus 1/1
Dermatobranchus ornatus -/1
Doriprismatica atromarginata 1/-
Flabellina rubrolineata 1/1
Glossodoris vespa -/1
Goniobranchus cf. reticulatus -/1
Goniobranchus daphne 2/1
Goniobranchus geometricus 1/3
Goniobranchus splendidus 3/3
Goniodoridella savignyi 2/1
Hexabranchus sanguineus -/1
Hypselodoris jacksoni 2/4
Hypselodoris obscura 1/2
Hypselodoris sagamiensis -/1
Jorunna sp. 3 -/1
Noumea norba -/1
Phyllidia ocellata 2/1
Phyllidiella lizae -/2
Phyllidiella pustulosa 1/2
* Pteraeolidia ianthina 6/6
Sagaminopteron ornatum -/3
Tritoniopsis alba -/1
Tylodina corticalis -/1
Phyllidia ocellata
Cadlinella ornatissima
Goniobranchus splendidus
Substrate - rich and diverse
Goniobranchus geometricus - anterior
mantle flapping
Hexabranchus sanguineus - juvenile
Sagaminopteron ornatum
Pteraeolidia ianthina - most numerous
Ardeadoris aff. averni - a pair
Hypselodoris obscura
Phyllidiella pustulosa
Goniodoridella savignyi
Tylodina corticalis
Hypselodoris jacksoni - juvenile - microscope
Hypselodoris jacksoni - juvenile - in situ
Flabellina rubrolineata - compare with below
Flabellina rubrolineata
Goniobranchus cf. reticulatus
Hypselodoris sagamiensis
Noumea norba
Jorunna sp. 3
Tritoniopsis alba