Barnaby Joyce (New England, National Party) Share this | Hansard source

Cyprinus carpio, the European carp, is one of the worst pests in Australian waterways. At times it is up to between 80 per cent and 90 per cent of the biomass. That means that, if you weighed everything in the river, between 80 per cent and 90 per cent of it would be carp. It's a great disappointment that I hear of the loss of Matt Barwick, who was in charge of the carp eradication scheme. I now feel that this scheme is stalling, and that is a very bad outcome. We were looking at the release of the CyHV-3, the carp herpes virus. It has 65 per cent and above mortality. This would have had a decisive effect on reducing the environmental pressures on so many sections of the river. They believe that because of the remarkable fecundity of carp this could be a one-hit wonder. I would like to note that, if we had that attitude with rabbits, we wouldn't have released the calicivirus or myxoma virus—and for prickly pear we wouldn't have released the moth. We have to at least give the rivers some chance of revitalisation. It's better to have a one-hit wonder than no hit at all. I note the mutation of viruses. If a virus does become ineffective because of herd immunity, you can always find the next strain to take over.

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