Saving Green & Golden Bell Frogs
For the Molonglo floodplain, regenerative land management could be the key to saving the last remaining population of the endangered Green and Golden Bell Frogs (GGBF) within the Southern Tablelands. Recent field survey indicates that this population may still be in decline.
Prior to European settlement, it is likely that the Molonglo floodplain was an intact valley filled with discontinuous braided flow patterns containing a complex of wet and dry grasslands, ponds and wetlands. Through the practice of agriculture and through major mining activities upstream, impacts on the floodplain include deep incision, deposition of mine tailings, stripping of nutrients and organic matter – all of which have negatively impacted the population of the GGBF.
The Mulloon Institute, in collaboration with Catchment Simulation Solutions (CSS), has investigated options to rehydrate and regenerate the floodplain via the introduction of a series of soft engineering interventions such as leaky weirs, baffles and minor cuttings to promote rehydration of the floodplain while at the same time improving water quality, reducing hydraulic energy and increasing attenuation of flow. The Molonglo Floodplain Rehydration Initiative also aims to improve and create habitat for the GGBF, including targeted areas for increased inundation and the preferred flow regime of wetting and drying.
CSS have assisted with the development of spatial hydrological modelling to inform how TMI’s work can contribute to the hydrological regime required by the GGBF and to assist stakeholders in seeing where water flows across the floodplain, pre and post proposed interventions.
Water Engineer Prawi Woods from CSS has recently achieved acclaim from his peers by winning several awards for his presentation on ‘Rehydrating the Floodplain to Save the Endangered Green and Golden Bell Frog’ at the 2021 Floodplain Management Australia National Conference.
Winner of 2021 Harold Sternbeck Medal
Young Floodplain Manager Outstanding Presenter Award
Prawi’s presentation gives a thorough overview of the Molonglo Catchment Rehydration Initiative including how the floodplain has been impacted by erosion from historical land use and how this has affected the local population of endangered GGBF. It also describes some of the challenges associated with undertaking the assessment, including how the floodplain rehydration was modelled and how the results were used to help communicate the future changes to the floodplain, and hopefully create a more resilient future for the GGBF population.
PRESENTATION: ‘Rehydrating the Floodplain to Save the Endangered Green and Golden Bell Frog’