 From around 2000, the Dole started to become infested by the alien plant "Crassula helmsii", also known as Australian Swamp Stonecrop.The plant began to significantly reduce the value of the nature reserve to wading birds, so in 2005 major work was undertaken to remove it.The Dole was drained, all of the surface soil was removed and the area treated with herbicide before being allowed to return to marshland.