By Chrissy SextonEarth.com staff writer
Plans to use a virus to control an invasive Australian carp will not work in the long term, according to researchers at the University of Exeter and the University of East Anglia. The non-native fish cause widespread environmental degradation, including impacts to water quality, that are damaging to native fish and ecosystems.
The carp are highly adaptable and their numbers have exploded over the last few decades in the Murray-Darling Basin, which is one of Australia’s largest freshwater supplies.
According to the Department of Agriculture, Water, and the Environment, common carp now account for up to 90 percent of fish biomass in some areas of the basin. Scientists have recommended for the government to approve the release of Koi Herpesvirus (KHV) to help manage carp abundance.
“The increased spread of carp and its impact on freshwater habitat has come at the expense of native fish species and aquatic vegetation,” the Australian agency explained. “The introduction of a biological control mechanism to tackle the pervasive carp problem will be an important complement to existing natural resource management and environmental watering programs that are helping to build the resilience of native fish populations.”
The Exeter team acknowledges that common carp must be controlled, but says that releasing KHV is not the answer. The researchers found that common carp would evolve resistance to the virus and the population numbers would soon recover. “Based on our findings, we believe the plan to control Australia’s carp with KHV is dead in the water.”
“Viral biocontrol is highly questionable and, as our study shows, it is unlikely to reduce carp numbers in the long term,” said Dr. Jackie Lighten. “Our modeling shows that even under the most optimal conditions for biocontrol, populations quickly recover.”
“Releasing KHV carries significant risks to human and ecosystem health, which likely outweigh the benefits, and we have previously urged further detailed research to avoid an unnecessary ecological catastrophe.”
Dr. Lighten previously argued in the Australian Senate that the country’s National Carp Control Program (NCCP) was omitting key areas of research from its work, including an assessment of whether the virus could even kill the carp, who have a genetic component of resistance to KHV.
Read on: https://www.earth.com/news/releasing-a-virus-is-not-the-solution-to-australias-invasive-carp-problem/