Mozambique tilapia (Oreochromis mossambicus) are listed in the top 100 of the world’s worst alien invasive species. Both Mozambique tilapia and black mangrove or spotted tilapia (Tilapia mariae) are established in Queensland. Their impacts on natural ecosystems threatens both fishing and tourism industries. The impact of tilapia is currently largely in Queensland but recent incursions in northern New South Wales have caused concern.
While we now have an effective surveillance tool (eDNA) developed under the stewardship of the Invasive Animal CRC for early detection and mapping the distribution of tilapia, current management mechanisms are inadequate for control of tilapia once an incursion has occurred. Indeed, it is now clear that current education programs are failing to stop the spread and options for management post-incursion are extremely limited.
Thus, there is a need to research, develop and evaluate potential tilapia control agents. Recently, the tilapia lake virus (TiLV) isolated from tilapia has caused widespread mortalities in Israel and Ecuador and since then has been reported in a number of other counties. This has raised hopes of the potential for tilapia biocontrol, however, prior to significant research investment in assessing this particular agent, it is prudent to evaluate tilapia pathogens in the context of biocontrol more broadly. Thus, this project proposes to conduct a review of tilapia pathogens and assess their potential as biocontrol agents.
The project receives funding from the Australian Government Department of Agriculture, Water and Environment
February 2021 update:
Tilapia Lake Virus has been considered as a potential candidate for biocontrol and has been proposed for further investigation. Another candidate for possible further investigation is the newly emerged tilapia parvovirus (TiPV), this virus has been reported to cause 60-70% mortality rate across six provinces in China, however the species specificity of TiPV has not been reported. All other potential pathogens assessed have been shown to not be species specific to tilapia and are therefore less suitable candidates for biocontrol.
A cost benefit analysis has commenced, this review seeks to identify the current distribution of tilapia in Australia, past and current management/control practices, existing impacts of tilapia on Australian waterways and the likely spread and impact in Australia based on current management systems.