Using local knowledge to understand seagrass decline in Corner Inlet, Victoria

The knowledge of local communities that work with and depend upon natural systems can provide unique insights into ecological processes and their relationships with human activities. Local knowledge can provide information for... [ view full abstract ]

The knowledge of local communities that work with and depend upon natural systems can provide unique insights into ecological processes and their relationships with human activities. Local knowledge can provide information for management that may be difficult or cost-prohibitive to obtain using scientific monitoring methods, such as creating environmental histories, documenting ecosystem-wide change and understanding natural ecological variability. Such information can alert managers of problems, spatially guide management initiatives or improve scientific studies investigating the causes of environmental degradation. We used local knowledge of commercial fishers to better understand the estuarine ecosystem of Corner Inlet, Victoria, where ecosystem health and fisheries productivity are strongly influenced by external sources such as land based activities and climate. Specifically, we documented seagrass cover change over the last few decades and related this to other major ecosystem changes identified by fishers. Contrary to previous work identifying Posidonia australis in major decline, we identified instead cover of Zostera nigracaulis at the smallest extent in memory of local fishers. Filamentous algal blooms were identified as a key threat to seagrass, where local knowledge enabled the mapping of extent and frequency of blooms. These results will be used to inform management priorities in arresting the seagrass decline in Corner Inlet.