Researchers' Diaries
Clay Bryce: Molluscs and Cruise leader, Aquatic Zoology
Kimberley Coastal survey – southern Kimberley Bioregion
Another year and another Kimberley survey, our third in the series. This time we concentrated our efforts in the southern area of the Kimberley Bioregion. The Kimberley Bioregion stretches from Cape Leveque, north of Broome, to Cape Londonderry in the very north, and is flanked by the Bonaparte Gulf Bioregion (Cape Londonderry to the WA/NT border) and the King Sound Bioregion in the south. We targeted a group of 12 islands/reef complexes between 15° and 16° South and 123° and 124.5° East. During this trip we conducted biodiversity surveys at 29 stations at locations including Wild Cat Reefs, White Island, the Champagney Islands, Beagle and Fraser Islands, and Irvine and Bathurst Islands, to name a few. For more information on what we found and our impressions of various sites visit the video tag of this website.
This inshore region was the most turbid to date, being a little more inshore of our 2009 survey. In fact we observed a fascinating oceanographic phenomenon during the expedition. It appears, and this needs to be clarified, that the huge diurnal tides prevent the sediment from settling to the bottom and, with the change of each tide, the sediment is moved along in a rolling wave, akin to a sand storm passing through the sky – very spectacular when viewed from underwater. During the transitions from high to low tide, the sediment wave appeared to be generated along the ocean floor, where current motion is the greatest. The turbid water rapidly ascended, engulfing the entire water column. Zoe Richards, in her diary entry, describes what it was like during her dive. From our experience undertaking marine surveys in this sector, there appears to be a very short window of moderate water visibility (approx. 20mins) over slack high tides before the sediment-laden water engulfs the reefs. It certainly made our surveys a challenge. However, this is not to say that all the dives were in turbid water. We were fortunate enough to find some clear water with fantastic coral cover at sites such as Brue Reef and at an unnamed outcrop northwest of Black Rocks. Although only with 12 m visibility it was like diving in a fish bowl compared to some of the more turbid site described above.
The team visited some very interesting reefs, recorded many species and now have a lot of work to complete before the next survey. This year however, we added the skills of Rodrigo Garcia from Curtin University to the team to undertake water quality. His data, when overlayed with our biodiversity information, will help to define why species are where they are. Once again we enjoyed a perfect run of safety and the weather was friendly – always a good thing!
Field Participants
WAM = Western Australian Museum, QM = Queensland Museum. AM= Australian Museum, HWA = Herbarium Western Australia (DEC), CU = Curtin University
| Clay Bryce (WAM) | Molluscs / Cruise leader/ dive supervisor |
| Aaron Cosgrove-Wilkes (WAM) | Molluscs |
| Merrick Ekins (QM) | Soft Corals and Echinoderms |
| Monika Schlacher-Hoenlinger (QM) | Soft Corals |
| Sue Morrison (WAM) | Fishes |
| Glenn Moore (WAM) | Fishes |
| Lynda Avery (AM) | Polychaetes |
| John Huisman (HWA) | Marine Flora |
| Andrew Hosie (WAM) | Crustacea |
| Zoe Richards (AM) | Corals |
| Oliver Gomez (WAM) | Sponges |
| Sam Bodie Field | Cameraman and standby diver |
| Nick Thake | Transect Videos and Diver |
| Rodrigo Garcia (CU) | Water Quality |
