Invasive Animals Issues
Animal welfare
All IA CRC research complies with the RSPCA policies (particularly relating to section D: Research animals and G: Humane killing). All research undertaken must be conducted in accordance with animal ethics approvals from state jurisdictions.
The IA CRC has also contributed to the development of codes of practice and standard operating procedures for humane pest control.
Infertility research
We are often asked about the potential for vaccines or oral delivery systems which cause infertility to be used as an alternative to lethal control. This type of research is ongoing, but is very expensive and time-consuming.
The ‘nirvana’ is for a gene-modification strategy to be developed which would then be passed on through a population by a virus. This methodology is called ‘virally-vectored immuno-contraception’. This technology is inherently complicated. Any genetic technology development is stringently regulated. Lengthy testing is required to ensure it is specific to the target animal and the methodology would be long-lasting and efficient once released into the wild populations.
In rodents, scientists were able to induce infertility in mice, but transmission rate of the virus to other mice was not high enough to be useful in wild populations. A similar approach was tried for rabbits, but in this case the infertility achieved was too short lived. The research that would be needed to determine a solution to these problems would be likely to run into many years and be prohibitively expensive. At present, this type of infertility research has been put on hold.
An alternative (non genetic) approach is now being taken. IA CRC researchers at CSIRO are testing an infertility vaccine for large mammals. The Gonacon™ vaccine has been developed in the United States and successfully tested in deer. It is also being researched by the USDA for further application in many other pest species from ground squirrels to elk and looks very promising. Trials have shown that in some species infertility can be induced for up to four years, and as the project extends this time frame may increase.
Here in Australia it has potential for use in kangaroos, camels, wild horses, donkeys and goats. However, simply distributing this chemical infertility vaccine in baits (broadscale) is not presently feasible. This is because many other herbivores are likely to find such baits palatable. For example, a baiting program to target over-abundant Eastern Grey Kangaroos would likely affect not only sheep and cattle, but also other wallabies and small native mammals that we would not want to sterilise.
At present, each each individual animal must therefore be captured and injected manually by skilled personnel. Unless we can develop suitable means of delivering this vaccine on a broader scale, there will be an ongoing and relatively high cost associated with this type of technology.
