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Wednesday, 17 August 2016

Our Dives in the Coral Sea

Anchored in sand
Larry and I have passed through about half of the time we expect to spend diving on the Coral Coast of Australia. It's our third trip here – 2006 and 2010 also saw us scuba diving and visiting various wild and lonely places along this coast. We determined in 2010 that the very best diving was far out on the reefs in the Coral Sea. So we left Rosslyn Bay on August 9th and headed the 120 miles offshore to the Swain Reefs.

We have a set procedure for getting in the water. Once all my gear is on and I've done all my safety checks, I wait for Larry (getting his gear on in the cockpit) to call out his safety checks at which point I take a giant step into the water. I normally hang onto the ladder and do various things like clearing my ears and looking around. Since we've been here, often we've been approached by large and curious fish – possibly looking for 'handouts' as at places like Bait Reef we think tourists feed them. So in the past we've seen large and beautiful fish like the humphead Maori wrasse (shown in previous Blog photos).

This time, I saw a cloud of tiny fish swarming under the bow and near them were about 8-10 fairly small fish – of about 30-40 cm or 12-14 inches. The most remarkable thing about them was their unmistakeably way of swimming. Sharks are cartilaginous and thus (minus a bone structure) can swim in a very menacing and sinuous manner. I also noticed that they had very large and coal-black eyes and a prominent lateral line. This is common with many species of fish and even whales with dark coloration above that line and light below (to make them inconspicuous predators if seen from above looking down at the depths of water, and to blend into the light when looking up at them). They were giving me cool appraising glances - unlike 'normal' reef fish – more like shoppers at an estate auction who are eyeing a handsome item they will never be able to afford.

It was just before the time that Larry splashed down beside me that I noticed a large prostrate 'fish' on the sand below and slightly behind the boat. It had a sharklike shape and I kept looking for the white or black tip on the dorsal fins which would confirm that this animal was a relatively harmless white or black-tipped reef shark. Instead I noticed that it seemed to have lines on its body … as it came up from the sand the lines seemed to meld into a type of camouflage pattern.

By this time Larry had confirmed that the 'small' swimmers under the bow were sharks and we decided the large 'fish' was also a shark. I asked him if he thought he could get pictures or a video … he was taking the video when the shark made a third pass beside us … coming much closer than the first two iterations. That's when we decided to climb up the ladder and out of the water and find a new divesite!

Looking in our two underwater guides later on, we discovered that we had come in close contact with a tiger shark.

Our two guides list about 40 prevalent reef sharks and do not provide any photos or description of the tiger babies. But the tiger shark is almost twice the size in length and weight (at 650 cm and 520 kg) of the other listed sharks (including hammerheads). The closest competitor is the Oceanic whitetip shark which is 396 cm. Previously, we have seen and taken photos along this coast of blacktip (180 cm) and whitetip (215 cm) reef sharks … we have not been worried by sharks. We once encountered a fairly large white-tipped shark which Larry had to repel with his camera. On looking at all our shark photos, we have re-discovered this big fellow and decided that he was most likely the Oceanic white-tipped … which (along with the Tiger) is listed as dangerous.

After reading about Great White Sharks in the July National Geographic, I have not stopped thinking about the (presumed) female tiger shark and her numerous offspring. I don't even know that this is what we had stumbled upon, but it makes sense to me. The Great White female named Gretel in the magazine article seemed to head for the same 'hub' each time to mate and give birth. Some sharks give birth to live young … there are also related animals (like the ratfish) who produce an eggcase within which the eggs develop. So I may be completely crazy about this, but my 'take' on the scenario we envisioned is that we saw a mother shark brooding a whole lot of dangerous little baby tigers. That makes sense of what we saw. Of course, The National Geographic mentions there are over 600 species of sharks.(and my guides only have about 40!) but I'm sticking with my story.

Another factor in choosing a divesite is to stay away from any fishboats. There was a tourist fishing operation near the 'Tiger' site. With about 8 tiny 'Dories' and a Mother Ship, you can imagine that a lot of cleaning of fish was going on over there. I suppose that we're lucky that Mommy was well-fed. Mind you, I doubt her maternal instincts are very well-developed!

We re-anchored 12 miles away, and decided that from now on if we are near a reef, we'll climb down the swim ladder and put our fins on in the water. That way we won't make shark-attracting splashes.

After leaving the Swains, we travelled another 120 miles out here to Frederick Reef. After spending about 20 hours standing watches and then getting anchored, we were hoping that even with some fairly strong winds in the forecast, we'd be able to dive here. The waves and wind kept getting stronger and stronger … the winds far exceeded the forecast and on the first night the anchor started 'dragging' … I got up about 4 a.m. feeling very very seasick for the first time in many years. The heavy winds and the motion during the high tide (when a fairly low sand island that we're in the lee of is swamped) continued. Each time the wind crept above 30 knots, the anchor dragged further. We kept expecting that (in accordance with the weather forecast) the strong winds would abate, but they only got stronger.

Blacktip rockcod
By the second night, with winds gusting to 45 knots we had to re-anchor in the middle of the night. My job would be to weigh anchor and then lower it again after we'd circled around and Larry (with the assistance of our outside screen) would yell for me to lower it again. It was pitch black outside while I crept to the bow. Larry had turned on the foredeck light but envisioning that I wouldn't be able to see down into the raging black waters to notice the anchor was actually at the surface, I kept a turned-on headlamp hanging by its strap between my teeth. After getting past the safety of the cockpit, I hooked onto the lifelines. Getting to the bow was good exercise as it was literally bouncing like an in-use trampoline in the waves. Larry joined me up there to get the 'snubber' off. This is a springy nylon line which takes the strain off the windlass after the chain is let out. Then he was gone again - back to the wheel - motoring into the teeth of the wind so I could get enough slack on the chain to be able to haul it up. Even so, the anchor windlass kept failing as it could not take the strain on it. I held on for dear life … constantly and rhythmically being immersed as the bow thrashed in the heavy waves.

Finally I could see the anchor just below the surface of the water and I signalled Larry. I had a long wait as he circled back into position. Luckily the water here is nice and warm (about 25degrees). When he called to me, I started letting the anchor down … as I neared the specified length of chain he came up to put the snubber on. Alas, the stainless hook snapped and the whole arrangement (including plastic-encased anchoring line) fell into the water.

A photo from Frederick reef
So that's how we ended up diving again - our 14th Ozzie dive in 2016. Larry noted where we lost the snubber, we swam under the boat towards the chain at the bow, and even before we swam past the bow we could see the snubber up ahead lying in the sand next to the chain. The visibility is just incredible. We look forward to having a memorable dive on the reef tomorrow!

At 8/15/2016 11:46 (utc) our position was 21°00.92'S 154°22.11'E

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