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| Originally Posted by TonyDragon Absolutely, that's exactly what I keep thinking. If they were planning on building a freeway through Wilson Prom or the Grampians there'd have been all hell let loose.
Very sad to hear about what's happening in Taz, I was under the impression that the fisheries down there were managed quite well, obviously not. I would actually love to come down and see the kelp forests, we're planning on doing it next year sometime over a long weekend.
Tony |
It's at it's worst around St Helens, although urchin barrens are starting to appear on the East side of freycinet and Maria Island, there's even a few small barrens (10-15M square) cropped up in Fortescue Bay, well to the Southern end of the coast.
As a fishery, the crays are quite well managed, their numbers are bouncing back quite nicely from their lowest levels in the mid-90s; the only trouble is that the fishery is managed to promote and maximise crayfish numbers of legal takeable size (105-110mm carapace length), rather than the optimum length (140mm+) for killing urchins.
That's all very well, but once you have a barren formed, everything's gone except for a fine growth of filamentous algae, so the whole ecosystem, including crayfish goes south; it's analogous with replacing a rainforest with a lawn, the urchins being the sheep which are the only thing that survive on the short grass and stop the forest returning.
The interesting thing is that the urchins don't seem to do much here in depths of less than 10m; I was in NSW recently, and the opposite was true, the urchins their weren't seen much below 10m but everything above was a desert and they looked like the identical species.
The local Blue Groper like em anyway.
