DAY/DATE
Friday
26/04/2024
SITE/S
Horseshoe Bay
Bowen
PARTICIPANTS
Julie & Terry
TYPE
Subtidal
MODE
Shore Entry
VESSEL
–
DIVE
1
SITE/S
Horseshoe Bay
SPECIES #
5
DURATION
114 Min
DEPTH/RANGE
3.7 m
TEMP.
26 C
VIS.
3 m
SURGE
Slight
CURRENT
Nil
COMMENTS & OBSERVATIONS
After our dive on Wednesday at Grays Bay where we had trouble seeing ourselves, never mind much else, we decided the visibility and swell at Horseshoe Bay looked okay when viewed from the Lions Lookout. This lookout is reached via a track from Horseshoe Bay and is part of the Cape Edgecombe Trail. An early start was in order to beat the forecast south-easterly winds and we entered the water through slight swell. Visibility in the shallows was limited due to the swell stirring up the sand, but once we reached slightly deeper water it improved. Our first search was along the southern headland and around the corner during which we failed to locate any sea slugs. Heading north-west we crossed the bay over the reef and once we hit turf algae covered rubble we started to find tiny slugs.
Whilst the surge made photography of these tiny critters a challenge, the visibility was pleasant and we were happy with our limited list of species.
Taxonomic Diversity:
Four of the five species sighted were nudibranchs and all were dorids comprising 1 x porostomes (a suctorial feeder – of the Phyllidiidae family), 3 x phanerobranchs (non-retractile gill), 0 x cryptobranch (retractable gill). A single Sacoglossan species completed the count.
Our Historical data:
– We have now completed 10 surveys and recorded 33 species at Horseshoe Bay since our first survey here on 12/06/2018.
– Our most frequently recorded species here are Gymnodoris citrina (50%), Samla bicolor (40%), Jorunna funebris (30%) and, Cratena simba (20%);
– This is the first occasion on which we have recorded Gymnodoris sp. 26 and Phyllidia sp. 04 at this site.
– There is insufficient data to suggest any seasonal or other trends with respect to our records of frequency or abundance of species.
– Our last survey at this site was on 16/11/2023
(Historical data courtesy of Terry Farr, who extracts it from his comprehensive database.)
Guide to Symbols:
+++ New Species
+ First time sighted in Whitsundays
# Most commonly sighted at this site with %
TOTAL SPECIES SIGHTED: 5
SPECIES LIST – ALPHABETICAL
Elysia sp. 30 -3
Gymnodoris amakusana -1
Gymnodoris citrina -1 #50%
Gymnodoris sp. 26 -2
Phyllidia sp.04 -1
SPECIES GROUPED BY ORDER
Nudibranchia
Dorids
Phanerobranchs
–
Gymnodoris amakusana -1
Gymnodoris citrina -1
Gymnodoris sp. 26 -2
Cryptobranchs
–
Porostomes
Phyllidia sp. 04 -1
Cladobranchs
Aeolids
–
Arminids
–
Dendronotinids
–
Cephalaspidea
–
Sacoglossa
Elysia sp. 30 -3
Umbraculoidea
–
Pleurobranchoidea
–
Anaspidea
–
