The Fisheries Department and recreational fishing representatives just got back from a jaunt in China and Korea where they were impressed by the use of artificial reefs that have helped in increasing fish stocks in these countries.
As a result, they are considering funding the establishment of new artificial reefs in WA .
Unfortunately, reading through the many objectives and outcomes of the tour, they have failed to examine one important factor – how similar is WA’s situation to China’s? The answer is not very. We have a hyper abundance of reefs, the problem is that there aren’t any fish on them.
WA’s coastal waters are made up of bands of limestone reef that runs for hundreds of kilometers along our shore, they used to be full of fish. So what is the problem? A lack of reef, or a lack of fish?
It is typical of past missteps made in fisheries management in WA. We assume WA is like the rest of the world when it is clearly not. We made the same mistake in the wheat belt, where clearing like it was Europe resulting in infertile saline wastelands over large areas that were once covered in massive woodland trees.
In the ocean environment, we have presumed you can fish like it is Europe, reducing stocks down to 30% or less of their virgin biomass and presuming that this will result in younger, faster growing fish rushing in to take their place. Unfortunately, the biology of WA fish says different.
In the infertile WA waters fish grow slowly. In many species, the big old fish we are wiping out wait for years until conditions are right to have their big breeding years. Smaller numbers of big old fish, not big mobile schools of young fish, repopulate the fisheries. Dhufish live to 40 years, and a one metre fish will produce as many young as eleven 60cm fish. Blue Groper live to 80 years, and change sex from female to male at 30 years old.
Similarly this proposal is missing the crucial difference. In the fertile seas fed by the mighty rivers that run out of Korea and China, the environment is very different to WA and lack of structure for fish may well be a concern in fisheries management.
But in WA, there are hundreds of kilometers of reef that should be covered in fish, but they are not.
Creating artificial reefs like it is China is not the answer to fisheries management in WA anymore than clearing like it is Europe worked for managing farming. However, paying attention to marine science and the biology of our fish will work.
The idea of trying to restock our waters from aquaculture tanks has also been mooted. This is an even more wacky idea. Whilst it has been successful in small areas like estuaries, lakes and rivers for smaller and easy to breed fish like bream or trout, trying to restock the expanse of the ocean with large fish is a pipe dream, unlikely to be effective and mind bogglingly costly compared with investing in better management and establishing marine sanctuaries.
Artificial reefs might be something to consider in the future, but whilst we are still ignoring the increasing consensus amongst scientists that marine sanctuaries that protect breeding areas and bring large fish back onto our reefs are the missing piece in conservation and fishing management in WA, they are a wacky waste of money.
Money that could be better spend on ensuring compliance with fisheries management rules and regulations like bag, size and boat limits.