Mike Scotland
The Land of OZ is a place of magic and wonder! We have Koalas, Kookaburras and Kangaroos. We also have eucalypt trees and a super abundance of flora adapted to our harsh climate.
The Sea of OZ is also a place of magic and wonder, possibly more so, for me, being a very passionate scuba diver.
Australia’s temperate seas have been geographically isolated since well before leaving Gondwanaland over one hundred million years ago from the Northern Hemisphere, by a band of warm equatorial waters.
As a result, more than two thirds of our marine fauna is endemic. That is, it lives locally. Most of the fish are unique to waters beneath the tropics. Our marine life is special and different. Diving in Sydney really is unique. We have fabulous marine treasure right here under our noses.
In this article, I want to highlight some of my favourite fish. Come along this journey with me and explore and enjoy the rich bounty Mother Nature has provided for our diving pleasure.
Rocky Reefs
As you descend into the dark waters around Sydney, you often see a pair of large bulging eyes of the amazing Banded Seaperch, Hypoplectrodes nigroruber. The name describes the black bands and red colouration. This fish lives around broken boulders where it can duck into a swim through or small cave. It is a master of its domain, perfectly well suited to life in shallow water. This Perch is so named because it has the habit of perching or ‘resting at fishy attention’ on its ventral and pectoral fins. They are very alert and look like they are about to rocket into motion at any moment.
They have four black bars, and big bulging eyes on top of their head. The red colour blends in very well with the reef as the red light is absorbed below nine metres depth. Red is a good camouflage colour.
Blue Devils
The most renowned cave dweller from temperate waters has to be the Blue Devil. They are one of the most beautiful fish, in my opinion. The Eastern Blue Devil, Paraplesiops bleekeri, is a largest of the family known as “Pretty fins” or Plesiopidae.
I have seen a pair of mating. The male does a special dance for the female reminiscent of a male Peacock. It is “the shimmy”. The male sets up a territory in a way similar to a Bower Bird. They have to have two or more escape tunnels. They venture out of the cave to feed and rarely if ever go out into the open. If danger is present, they can retreat along a rock wall behind the protection of boulders back to the safety of their sea cave.
Blue Devils have translucent golden pectoral fins, enormous ventral fins and a yellow caudal peduncle. They have large, oversized dorsal and anal fins. There are bright blue spots on their head. The whole show is an electric neon light show; simply dazzling!
Flathead
Our local Tasselsnout Flathead (Thysanophrys cirronasa) has a large bony head with a mouth as big as a duck billed platypus, shaped like a giant scoop. Its enormous eyes have tree-like fringes called an iris lappet growing over them. This helps with camouflage, disrupting the eyeball. It has huge pectoral fins and strong venomous dorsal spines. There are spines on the head as well. Their body is quite small.
They can change colour to blend in with the ubiquitous red cement algae that covers all of the rocks in NSW. These Coralline Algae encrust many or most of the boulders everywhere. That is why they look pink! Australia has about three quarters of the world’s flathead species. It is a world hotspot for Flatheads.
Blue Gropers
Blue Gropers are easily the friendliest fish in the sea. The big bright blue males are inquisitive and unafraid. They were almost wiped out by overfishing and spearing until they were protected. Now, they are common and become so used to divers that they follow us around for the whole dive.
Eastern Blue Gropers are not Gropers but are a type of Wrasse, Achoderon viridis. They are all born female. During this phase, they are a dull brown colour. When they become male, they change to bright blue. Their big lips and stumpy teeth enable them to smash up sea urchins easily.
Summary
Sydney’s unique marine life is very special indeed. I run an on-line scuba diving magazine called Dive Log Australasia. Its mission statement is to celebrate the beauty of our oceans and educate marine lovers about Marine Biology. www.divelog.net.au
All photos: Mike Scotland
Editor’s note: Mike also has two books documenting the marine life of Australia, with spectacular photos. Contact Mike directly to order your copy.