Well scientific research has built up a large amount of knowledge about the Crown-of-thorn
starfish. So it's a native species on the Great Barrier Reef. We also know that it goes
through large population fluctuations. It's a species called a boom and bust species.
So it's a bit like locusts. Sometimes its populations are small and other times a population
explosion takes place and since their sole food is coral flesh that's when they do the
greatest damage to reefs, especially the Great Barrier Reef.
Crown-of-thorn starfish are responsible for about 40-42% of the mortality that's been
seen on the Great Barrier Reef over the last 30 years. So it's a very significant proportion
of the damage that we see. Well Crown-of-thorn starfish just looks like
any other starfish except it's got all these magnificent spikes on it. They're around about
dinner plate size. They can eat a dinner plate full of live coral polyps every day. We find
them stacked up three or four deep when they're aggregating. We had one reef that we took
80,000 Crown-of-thorns off. Recently use science to improve the control
methods so it now only requires one injection to kill a Crown-of-thorn starfish rather than
in the past it would be 20 or 30 injections into each arm.
The sites that have been controlled so far, there's something like 120 sites and actually
coral cover has been maintained at more than around 90% of those sites which is a really
important outcome. So that's important for the tourism industry but it's also very important
from protecting recovery of coral reefs from other impacts that it might be affecting.
We've got a team of 32 people doing the work right now as we speak. We've put a lot of
time into training the divers so they won't break the coral but also so they won't kneel
on any Crown-of-thorns. Maintaining the coral is the key. It's not how many Crown-of-thorns
do we kill. It's really how much coral can we protect and how much will that benefit
the reef in the years to come. Of course we've got to have good coral cover to have good
spawning and good recruitment and longevity on the reef. And that's part of what this
program with working on Crown-of-thorns is all about.
So the only mode of controlling them is by physically removing individuals or physically
injecting lethal injections of individuals one by one. And when you have a population
outbreak of millions that takes a lot of effort. So our research is trying to focus on whether
there's a more effective way, cost effective in both financially and labour, to cull large
numbers of Crown-of-thorn starfish when they're in an outbreak mode.
It's a stunning and wonderful place to enjoy and again, I think the Crown-of-thorn starfish
control program is one way that we can look to making sure that that kind of experience
is available for all the millions of people that come to visit the reef every year and
for generations to come. I love it and I love it because I know we're
making a difference and it's the course of that and my staff just see that what we're
doing, we are protecting the reef. It's a good practical outcome.
The reef is absolutely spectacular, one of the seven natural wonders of the world and
it's been left in the hands of Australians to protect and I'm very, very pleased to be
one of those people who is out there practically delivering that.