Various methods in the 20th century have been attempted to control the Australian rabbit population. Conventional methods include shooting rabbits and destroying their warrens, but these had only limited success. In 1907, a rabbit-proof fence was built in Western Australia in an unsuccessful attempt to contain the rabbits. The" myxoma virus", which causes myxomatosis, was introduced into the rabbit population in the 1950s and had the effect of severely reducing the rabbit population. However, the survivors have since adapted and partially recovered their previous numbers.