- Biological control
Mustering is when a herd of goats are found and are rounded up (either by man on horseback, man on motorbike or helicopter) and sold as pets or as pet food. There are many buyers in the Australian market, as there are many feral goats that are valued for their fur/hair/fleece. For example they have exquisite cashmere and mohair.
Another type of mustering is called the ‘Judas Goat’ method. A stray, feral goat is caught and a radio-collar is fixed to the animal. When released, the goat would join up with a feral herd. Using signals transmitted by the collar, it would be tracked down and the entire herd would be shot, except for the ‘Judas goat’. Then the goat would go in search for a new herd and the process would start over again.
Like most operations, culling is the most effective form of shooting. This is the mass killing of a selected species. In most cases this is the humane thing to do, as the animals are starving or dehydrated, due to lack of resources which they have exhausted.
However in some cases, e.g. Townshend Island, other control methods, e.g. Biological Control, have annihilated the populations as much as possible and there are a few left. Park Rangers, or people of similar positions, hunt and shoot the animals in the hope of totally eradicating them from that area.
Trapping includes goat-proof fencing. In the desert and the more barren grasslands, goats need a lasting source of water. Concentrating on these areas, one-way fences are built and can trap many goats, as there are no possible escape points, but there are several entry points.
The Dingo is the goat’s main predator. It can control the feral goats sufficiently enough except in the rocky, sheltered habitats. The goats in these areas have refuge from the dingo. These particular areas are steep, rocky ledge-like outcrops.
In rural areas, with the goats living in sheep and cattle grazing land, the Dingo has been removed by the farmers. This has been due to the threat of dingo attacks on the farmer’s livestock.
Wedge-tailed Eagles are also predators of the goat.
Immunocontraception is currently being investigated by the CSIRO. If they decide that the fertility agent would be virus-like, carried by a vector, then the agent must infect the dominant males to have any effect.
Also, if the CSIRO decides that it would be in the form of a virus, the domestic goats would also be effected therefore costing the industry millions of dollars, so they would have to develop an immunization agent, so the ‘virus’ doesn’t effect the domestic goats.
The introduction of an actual virus quite possibly would devastate the feral population, along with the domestic population. Once again, the CSIRO must come up with a virus that will only affect the feral goats, and then an immunisation agent for the domestic goat herds. Imagine if a couple goats escaped that were immune to the virus then the feral population would eventually become immune and the virus not be effective anymore. Clearly this alternative is not a good option.