For anyone who dives in the Gold Coast Seaway you would very well know about the death-defying Stonefish.
The most common species found along South East Queensland is the Estuarine Stonefish (Synancia horrida).
For those who don't know much about this species, allow me to enlighten (and scare the crap out of) you...
This species holds the title for being the most venomous fish in the world! These ridiculously well camouflaged hunters lie patiently in wait for unsuspecting prey to pass close enough for them to strike. One of the most identifiable elements of a stonefish is by their large paddle like pectoral fins that they use to dig themselves into the ultimate ambush position.
So how does such a frumpy, slow-moving fish defend itself? With numerous spines along its dorsal fin that act like syringes, of course! Theses spines deliver a highly toxic venom. The multicomponent venom has neurotoxic and myolysin effects. So basically if your stung, your nervous system and muscle control are, for lack of a better word, screwed. Most dangerous of all, this toxin has direct effects on the heart and blood vessels. So to summarise this, if you are to be stung expect to experience; severe, intractable pain followed by localised swelling at the puncture site. Oh and of course dizziness, nausea, vomiting and progressing on to collapse and breathing difficulties. If this sting is not treated it can result in death.
The thing that possessed me to write a blog on these guys was because myself and a few students from Uni had an unexpected encounter with one. We were given a permit to do some research in the Gold Coast broadwater with a seine net. Our objective was to look into the levels of 'piscivory' (fish that eat fish) and assemblages of the fish that inhabit these shallow waters. We tested this early in the morning and late in the evening - this was to ensure we didn't miss any species that may be dormant during the day or night.
One night, we were walking a net at shoulder depth and as we began to head up onto the shore the net seemed to be significantly heavier than our first few runs. We would often pull up many twigs, branches and a couple of rocks so a heavy net wasn't all that unusual. On closer inspection of our net we found a rock, a large rock, a large rock that moved!
We gently and extremely carefully picked him up and placed him back in the water.
While the Stonefish seem to be nothing but a mean, spiny venom machine I would like to add how incredibly manufactured these animals are. I often see them while diving and the detail in their camouflage is something to be admired and unlike reptiles, insects and arachnids, which use their venom for offensive purposes, the Estuarine Stonefish only use their venom as a defensive tool. So... just dont step on it and you'll be fine!
That night we still had around 4 runs to go... and wearing only very thin dive boots we were all a little hesitant about wading our way back in the water!
Sarah Shark www.sarahshark.com