The devastation of swathes of the Leeuwin-Naturalise National Park near Lake Cave in 2021 has had an unexpected significant benefit. The Margaret River-Busselton Tourism Association has reported water levels in one of its biggest subterranean attractions is now at the highest levels seen in decades as a result of the December 2021 Calgardup bushfire. The result is a dramatic turnaround from the mid-2000s when rapidly-declining water levels were feared for the cave and the health of its tiny inhabitants. MRBTA’s Capes Foundation director Steve Harrison said normally the dense vegetation around Lake Cave absorbed rainfall before it flowed through into the cave system. Instead, visitors to the MRBTA attraction were being greeted with fresh underground water levels justifying the cave’s name. “The water in the cave’s lake originated as rainfall on flat ground about one kilometre or two kilometres to the east,” Mr Harrison said. “It is now making its way through the limestone ridge towards the coast, where it emerges as springs, including the one at Conto Spring beach. “This event clearly demonstrates the interconnected nature of our environment and how changes in above-ground vegetation impact the water levels below-ground.” Water levels at MRBTA caves have been studied for more than 15 years, recording fluctuations in water levels based on changes to vegetation. However, in encouraging visitors to take in tours of the site as soon as possible, Mr Harrison said it wasn’t possible to predict how long the levels would remain high. The news buoyed MRBTA veterans who have long toiled to protect the health of the region’s karst system, of which they are key custodians. In 2005, hydrologists first noted alarming declines in water levels at several caves, including Lake Cave. Those concerns kicked off major studies as well as the Lake Cave Eco-Hydrology Recovery Project. Apart from the loss of a major attraction which has drawn visitors to the region since the late 1800s, declining water levels also threatened the caves’ resident stygofauna which relied on a moist environment. A series of actions were undertaken at several caves in 2010-11 funded partly by the State Government that included installation of trickle-release storage tanks and using plastic liners to hinder falling water levels.