The forecast all week sounded brilliant, light winds and only a very small swell. Friday night I boarded Big Cat Reality at her base at Scarborough, unpacked my dive gear on the huge rear dive deck and selected a comfortable bunk for the weekend.
Big Cat Reality is a 25m long catamaran, with a massive 10m wide beam. She has 24 bunk style beds for passengers, and 4 for crew. Each weekend her crew take a group of divers to explore the wonders of the Moreton Bay Marine Park.
After stowing my gear I ask Gil, our skipper, what the latest forecast was. He informed me that it didn’t sound very promising, with the westerly winds picking up over the weekend.
After all the divers were onboard, we were given a safety briefing by Gil, and a dive briefing by the Divemaster. Departing Scarborough, the bar was opened, supper served and a DVD played as we headed across Moreton Bay to our overnight anchorage near Moreton Island.
Early in the morning Big Cat Reality pulled up anchor and then headed to the outer side of Moreton Island. I got up to watch the sunrise and was greeted by a brilliant day, flat seas and only light winds, perfect winter diving conditions.
Our first dive was to be at China Wall, a site on the outer side of Moreton Island that is generally only dived in calm conditions. This site is also a grey nurse shark aggregation site over winter and fully protected from fishing by the Queensland Government. As such, our dive brief also included a run down on the ‘Code of Conduct’ for diving with these critically endangered sharks. Just prior to the dive a humpback whale surface right beside the boat, which made everyone eager to hit the water.
Being first in the water I found there was a slight surface current, but the visibility was easily 20m and the water temperature was 20C degrees, winter diving in Brisbane is very hard to handle. We then descended to explore the rocky terrain at China Wall.
In depths from 16m to 29m we explored gutters, ledges and caves, decorated by hard corals, soft corals, black coral trees, gorgonians and kelp. There are only a hand full of dive sites off Brisbane where kelp can be found, and it is bizarre to see this brown swaying kelp growing alo
ng
side hard corals.During the dive I encountered a number of turtles, a range of resident reef fish, wobbegongs, sweetlips, crayfish and an assortment of invertebrate life, but no grey nurse sharks. After exploring a number of gutters we stumbled across a large swim through arch. This impressive arch is 3m wide by 8m long, with a ceiling covered with tubastra corals, sponges, gorgonians and black coral trees. We didn’t get onto the main wall at the site, which drops down to 35m, it will have to wait until the next time I explore this fascinating dive site.
Our second dive was at Cherub’s Cave, even further south on the outside of Moreton Island. More humpback whales were seen, and during the weekend almost every dive brief was interrupted by a humpback surfacing right next to the boat. Cherub’s Cave is another protected grey nurse shark habitat, but again none were seen today.
With a light surface current we quickly descended onto a large rocky outcrop in 16m. This outcrop drops to 25m and is surrounded by kelp beds, which hide four entrances into the cave. Even though the cave is quite large and can hold a number of divers, I decided to stay outside today as I was test-driving my new digital camera.
My buddy Cameron was also trying out a new camera so we slowing swam over and around the outcrop looking in every ledge, crevasse and gutter for photographic subjects. These were not hard to find, and we were soon shooting images of nudibranchs, anemonefish, scorpionfish, crayfish, hawkfish, butterflyfish, surgeonfish and of the hard and soft corals. The best subjects were a dozen spotted and ornate wobbegong sharks lazing around on the top of the outcrop, all in the range of 1.5m to 2.5m long.
After a huge lunch, the meals always being a highlight of a Big Cat Reality trip, we headed up to the rarely dived Brennan Shoal. With the wind starting to pick up, the seas were getting choppy, but with no swell it was only a minor inconvenience. The visibility at Brennan Shoal was only 12m, but we got to explore an interesting rocky reef in depths from 16m to 20m. There were many gutters and ledges to investigate, and a nice collection of coral to be seen. I concentrated on the smaller critters seeing several species of sea stars and nudibranchs, plus goatfish, hawkfish, fairy basslets, lionfish, scorpionfish, lizardfish, pufferfish and wrasse.
The afternoon dive was on one of Brisbane’s most interesting shipwrecks, the Marietta Dal. She was a 7500 tonne liberty ship built in the USA in 1944. In May 1950, the 140m long ship was carrying a cargo of sulphur, oil, tractors and other general cargo when she ran aground on Smith Rock. Any hopes of salvaging the ship and cargo were quickly abandoned when she broke in two.
Completely broken up, the remains of the Marietta Dal are now found in 10m to 18m and make for a fascinating dive. The visibility was again 12m and there was quite a surge on the site, however we still had fun looking at the wreckage of plates, beams and the prop shaft. The most interesting part of the wreck is the cargo of tractors, which look like small tanks with their caterpillar tracks.
With the wind becoming more brisk we anchored for a night dive behind Flinders Reef at a site called Mary’s Lair. After four dives I was content to relax and watch a DVD, while those that dived had a great time. Plans to shelter for the night behind Moreton Island were quickly forgotten as the anchor was stuck. As we were in a very sheltered location it wasn’t a drama, and it was thought best to deal with the anchor in daylight.
The next morning we woke to 30-knot westerly winds, white choppy seas, but fortunately no swell. Very few boats would be heading out today, but since we were already out here we had to make the best of it. Our anchorage at Mary’s Lair was probably the calmest spot around, so it was decided that we should just dive here.
Even though it looked like a wa
shing
machine on the surface, under the waves it was calm and clear, the visibility
easily 20m. On our descent to the bottom we were surrounded by a massive school
of barracuda. Over a hundred of these impressive fish swam around us for the
first few minutes before disappearing into the blue. Exploring the wonderful
coral reef at this site, in 10m to 18m of water, we encountered wobbegongs,
turtles, a school of squid and a wealth of reef fish and invertebrate species.With the anchor tightly wedged into a crevasse, it was decided to do another dive at this site, while the crew worked out the best method to raise the anchor.
I again explored under the boat, looking for photo subjects, which were in abundance in the coral gardens. Nudibranchs, sea stars, a large anemone packed with anemonefish, moray eels, hawkfish, scorpionfish, grubfish, angelfish, butterflyfish, pufferfish, surgeonfish, morwong, sweetlip and many other species. At the end of the dive I even found a beautiful pineapplefish under a ledge.
With the anchor raised, and the wind increasing in speed, it was decided best to abandon the final dive of the weekend, as it was going to be a bumpy ride back to port. Big Cat Reality punched through the sloppy waves with ease, while we sheltered inside watching DVD’s, wrote up logbooks and viewed our digital images.
Even with less than ideal conditions, we had a wonderful weekend on Big Cat Reality diving the Moreton Bay Marine Park, seeing the best and worst of Brisbane winter weather.