If the problems associated with Carp are not dealt with, these fish present a future risk to both society and the environment.
Carp are bottom feeding fish which filter through the sediments at the bed of the river. They suck up the sediments along with any nutrients contained in them and then filter out the unwanted materials through their gills. This feeding process results in displacement of a significant amount of the materials at the bottom of the river.
This process can undermine river banks and increase the erosion, resulting in unstable and collapsing land at the edges of the river (seen in figure 4). In the future, this could be potentially hazardous to the many houses which are located near the edge of the river. If the river bank was to be eroded too far, this could disrupt the stability of the housing infrastructure.
Much of the river is also surrounded by steep cliff faces. If the base of these cliffs were to be undermined, these cliffs could become unstable and cause a very large hazard to anyone in the area.
Carp currently make approximately 90% of the fish population in the River Murray. Due to insufficient food and murky water caused by carp the native fish populations have decreased and are still falling. Carp are very robust fish which can survive in most environments and this ability allows them to continue living while the native fish can not.
If carp are not dealt with, the native fish in Australia have the potential to completely die out which would have a dramatic effect on the ecosystem.
Carp have become a significant problem in the river ecosystem and a possible solution to the issues they’ve caused has been proposed.
In 2016, the Australian government allocated $15 million into a plan to control the carp numbers. The proposed plan was to introduce a highly contagious herpes virus into the carp population in the river Murray. This virus has been simulated so that it only infects the common carp species and will not be contracted by native fish.
This solution however holds a high risk for the future if it is implemented. Experts say that ecosystems could be disrupted by the amount of dead carp which will surface. The amount of oxygen loss caused by the millions of tonnes of rotting carp could disrupt vital ecosystems and lead to unpredictable consequences.
Another risk is that some believe tests in a lab can not ensure that the virus will not infect native fish in the river. This virus is likely to be only a short term solution and not keep carp numbers down forever and some think it is not worth the risk of killing off native fish for a short time of decreased carp population.
Geohazard 