On the 24 November, members of the Murray River community came together to learn about how they can be involved in a new and exciting project that focuses on promoting the growth of Black Pygmy Mussels (Xenostrobus securis) in the Murray River to provide a food source for black bream.
Through PHCC’s Fish Friendly Farms project funded by the Royalties for Regions, 45 members of the Murray River community attended an informative workshop recently at the Pinjarra Community Hall to learn how they can direct their interest and love for the Murray River and Peel-Harvey Estuary into a citizen science project monitoring populations of the Black Pygmy Mussel in their own backyards.
Black Pygmy Mussels are native to southern Australia, where they are particularly abundant in the brackish intertidal zones of rivers and estuaries. This species can provide a variety of ecosystem services ranging from providing habitat for native finfish to the removal of nutrients from the water column. They are short lived (1-2 years) and have a preference for shaded areas and hard structures such as roots of riparian vegetation under banks as well as the underside of snags.
They are an important food source for black bream, a native species of fish that completes its entire life-cycle in the estuary in which it was spawned, in this case the Peel-Harvey Estuary System, including the Murray River. Research by Dr Alan Cottingham from Murdoch University in the Swan-Canning Estuary suggests the decline in abundance of black pygmy mussels was accompanied with marked declines in the growth and body condition of black bream
Following presentations by Dr Steve Fisher (PHCC, Program Manager, Science and Waterways) and Alan about the benefits of the project to the overall health of the waterways, including the Ramsar 482 Site, and in particular for our declining black bream stocks, most of the attendees at the community meeting registered their interest in taking part in the citizen science program. This summer each Citizen Scientist will attach a basket seeded with Black Pygmy Mussels onto their jetty (or one owned by a friend) in the lower reaches of the Murray River downstream of the weir. The basket will act as a substrate for the mussels to attach to, and if conditions are right, over the course of a few months form a localised colony of Black Pygmy Mussels in each. The tendency of the mussels to colonise and their survival rate will be largely driven by the salinity of the water: because the Murray River generally increases in salinity from the weir to the estuary, this trial will show us the ideal range for establishing the mussel colonies along the Murray River.
This project is closely linked to two other projects currently under way in the Peel-Harvey Estuary: The stock enhancement of black bream, delivered by PHCC in partnership with Murdoch University and John Tonkin College, and the Community Shellfish Gardening Project delivered by The Nature Conservancy through funding from Alcoa Foundation and supported by PHCC. Together through these projects we hope to improve the health of our waterways through direct involvement of the community as custodians of one of our regions greatest natural assets.
This project is supported by PHCC through funding from the State Governments Royalties for Regions, the Alcoa Foundation’s Three Rivers, One Estuary Initiative and the Australian Governments National Landcare Program.