A juvenile Big-eye Emperor made an appearance in the aquatic reserve today, as did a coral snapper species that I haven’t identified yet, but possibly a juvenile Red Bass. With the water temperature slowly decreasing, today 20 degrees, many of the tropical visitors have now died off. Plenty of butterflyfish, surgeonfish and more hardy tropicals remain though. Each year more and more species arrive, pushing their distribution limits, and providing anecdotal evidence of ocean warming.
Having seen the vibrant colours of Sydney city as the Vivid festival commenced last night, the underwater natural world presents a colourful alternative all year round. As well as a solitary Weedy Seadragon today there were an abundance of corals and sponges decorating the seabed. The seadragon is a bit lonely at the moment – this individual being the only one that has been seen, in months of diving in the aquatic reserve, and can be identified by the single appendage on the head.
A building swell from the south found me in a different part of the aquatic reserve from usual and with poor visibility and an uncomfortable surge underwater I stumbled across some beautiful hard coral I haven’t found before. A large head of coral, full of tropical fish, mainly two species of Dascylus, even crabs.
Surely evidence that the Great Barrier Reef is heading our way as waters warm up, several heads of this coral appeared to be very healthy, and the lower fish in the photo is the first time I have seen this species of Headband Humbug (Dascylus reticulatus) in Cabbage Tree Bay Aquatic Reserve.
This little blue fish is another of our tropical visitors that belongs to the Damselfish family and only about the third I have ever found. The tiny juveniles are found hiding amongst rocks. With water temperatures starting to drop below 20 degrees many of the tropical visitors to the waters around Sydney will start to disappear in the next few weeks.
The eastern blue devil is a secretive reef fish, usually found hiding under ledges or in caves, and favouring slightly cooler water, so often seen at greater depths. It is one of the few protected species in NSW due to its scarcity.
It is also my dive buddy Matt’s favourite fish so we were both excited to see this one out in the open today. It’s striking colouration makes it popular with those underwater photographers lucky enough to find them.
Despite the somewhat drab name this fish is far from it. The juvenile has an exotic body shape with elongated dorsal and ventral fins. The body is adorned with white stripes and rich purple colouration. This one has had a nip taken out of his tail. Seldom seen in the aquatic reserve this tropical visitor is only usually seen in its juvenile form. They can be found hiding amongst weed or amongst the rocks.
This beautiful Butterflyfish, sometimes called a Longnose Butterflyfish, is a very rare visitor to Cabbage Tree Bay Aquatic Reserve. I have only ever since it twice in Sydney but on this dive I found two swimming amongst the rocks. They only ever seem to appear just before the onset of winter, before the water temperature gets too cold for them (below 20 degrees). They are tropical visitors and Sydney is pretty much the limit of their range