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FOSSIL CAVE / GREEN WATERHOLE CAVE (5L81) BONE RETRIEVAL DIVES FOR DR TREVOR WORTHY (UNIVERSITY OF ADELAIDE), 27/28 MAY 2006. PARTY Peter Horne (Team Coordinator), Neville Skinner (underwater photographer/ support & safety Diver), David Albano (support/safety diver) and Mark Nielsen (safety diver); Ian Lewis (surface support). OBJECTIVES To attempt to relocate 1979 Flinders University survey star-dropper posts along the “N” line, especially N3 dropper, and an adjacent labelled tag known as “Aslin Site 12” (“Site 07” during the 1979 project); to attempt to photograph the area before, during and after any bone-digging work; and to collect samples of bones and sediment around Tag 12. Carrying gear down to the cave’s lake which is situated in the dark alcove behind the two scuba cylinders at the far end of the collapse (Peter Horne). The research party (left to right): Neville Skinner, Ian Lewis (surface support), Mark Nielsen, David Albano and the author (Dave Albano/Peter Horne). OUTCOMES Dive One: Saturday 27 May 2006 (duration approx. 45 minutes). Peter and Neville descended first through the “Letterbox” with a large open reel of thick white synthetic rope with the intention of locating and securing the old N3 star-dropper. The water was noticeably dark and murky, suggesting that crushed grass observed around the carpark area was most likely caused by a group of other divers earlier that morning, which was unfortunate from the point of view of photography. The water level was also lower that Peter had ever seen, and there was a substantial air section extending into the normally-flooded ceiling area of the cave. Their first observation during the descent into the gloom was that none of the marker tags remained on the star-droppers which were located, and many of the droppers had either disappeared or fallen over (some were later found to have corroded right through at their bases, leaving just a rust-filled hole in the rock). The lines which had previously linked the main droppers together were also missing and it took around 5 minutes before the correct line of droppers was relocated. As Peter approached what he believed was the N3 dropper he was pleased to see the yellow Site 12 marker floating off the bottom exactly where it was expected to be, despite the 18 years which had passed since the last mapping project he had coordinated there back in 1988. Running the thick white safety/reference line down into the main chamber along the original “N” line (Neville Skinner). Peter tied the white line to N3 and proceeded to assess the area while Neville took photos, and because he only had some small helmet-lights for illuminating the scene, David and Mark supplied additional side-lighting for this task. A fallen dropper (believed to have been N1 or N2) was found rusted through at the base and leaning against the back wall, just over a small deeper hole, and Peter collected some of the more obvious (and smaller) bones and carefully scraped samples of the sediment into a 2-litre plastic ice-cream container using its flat lid, minimizing hand contact as much as possible. Tying off the white reference/safety rope to (presumed) star-dropper N3, about 1.5m beyond which Tag 12 can be seen floating in a small area of flatter calcite-covered silt (Neville S). The first container (#1, blue) was used to hold material which was collected from within about 2-3 metres of Tag 12 (around 9 metres depth), with some slightly shallower samples included. No obvious bone material was seen below Tag 12 and the floor in this area basically comprised a 2-3m wide flatter section of boulder, with a fairly thick deposit of calcite rafts. Collecting sediment and bones (Neville S). Container No. 2 (gold) was used for material which was collected considerably shallower than the Tag 12 location, virtually directly above and over the boulders at a depth of about 6 metres close to the N4/N5 pegs (visible in the photo below), after Neville had located a partial skull in the silt there. Container No. 3 (blue again) was used to store more bones which were also within a 3- 4m radius of N3/Tag 12, and bones found included many thin, long bones and a few larger ones including two which are obviously from large mammals such as kangaroos. Sample 2, using a yellow container, near N4/N5 (pegs visible near boulder in left photo – Neville S). Sample 3 (blue container) to the right of Tag 12, and placing the samples into the wire bone basket for transporting back to the surface. Note the reduced visibility (Neville S). This first dive was disappointing to some extent with regards to the poor visibility and the scarcity of good bone-fields near Tag 12, but it was a safely-executed and interesting dive nonetheless and provided important preliminary information for possible future work, which should ideally include more photography and silt/bone-collecting around N3/Tag 12 as well as sediment sampling directly below Tag 12 (at the wall/floor interface) and a closer exploration of the deeper small holes in that area which escaped earlier mapping documentation. Dive Two: Sunday 28 May 2006 (duration approx. 45 minutes). The dive party comprised the same divers as the previous day, but Ian was not in attendance this time. The weather was atrocious but the water was spectacularly clear, and it was a very easy task to relocate Tag 12 (a standard cave diving line/reel was used this time instead of the thick white rope). Peter descended first with David and both divers collected more material/samples around Tag 12, storing their samples in three white ice-cream containers which like the smaller ones of the previous day, were carried down to the site in a bone-collecting basket (wire cage with split-pin lid, used during the original research project by SAUSS Inc). Container No. 4 (marked “Pumpkin Soup” – hopefully nobody will believe the label!) was taken down to about 11 metres where a small area of wall/floor interface had collected some sediment, which was carefully scooped into the container. This was below and slightly to one side of the Tag 12 area of interest – any material which had fallen straight down from Tag 12 would likely have fallen down through some small deeper holes which require further investigation with single or side/mount scuba cylinders or the like. Container No. 5 (unmarked) was basically another general sample close to the previous day’s #3 container collection on the flat calcite area to the right of Tag 12, and Container No. 6 (marked “Soup 5/7/00”, see above warning!) was at a depth of 6m where David had spotted some interesting skeletal bits and pieces under the edge of a slab. During this collection Peter realised that a fallen, nearly-buried dropper there still had the original tag N4 loosely attached; this was removed and placed in the container to assist later labelling. Collecting bones and sediment from along the edge of the boulder near N4/N5; the unlabelled standing dropper is N5, and N4 can be seen lying to its right (Neville S). At various times during this dive Neville took more photos, and after the samples had been taken to the surface Neville took Peter and Mark back down to the deep floor-hole area to show them additional cavities and bones which await collecting and recording in the future. At the conclusion of the diving and collecting activities the larger bones were wrapped in wet newspaper (in hindsight, not a good idea for possible DNA studies, in view of the paper and ink base, but that’s how the earlier Flinders teams did it) and the other containers were padded and stacked in a plastic Esky to keep them cool and protected for the journey back to Adelaide University, where they were delivered by Peter to Dr Worthy on Monday 29 May 2006. Preliminary assessment indicated that some bones could be of considerable interest and hopefully further more detailed research may come from these efforts in the not- too-distant future. Peter Horne, Team Leader (former Projects Coordinator, South Australian Underwater Speleological Society Inc; Project Leader of SAUSS Project No. 1, Fossil Cave, 1988 and former Manager of Mapping & Research, Cave Divers Association of Australia Inc.) .

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