Healthy fish and waterbird populations in the Coorong need to be supported by a healthy foodweb in which food items exist in sufficient quantities and qualities (that is, high energy) and are accessible. Changes in water levels and water quality in the Coorong over time have altered the composition and availability of food resources for important species such as fish and waterbirds.
What we are doing
Research is currently being undertaken to better understand the primary food sources for key fish and waterbird species in the Coorong, the availability and nutritional value of food, and the habitat requirements of those food sources, which include macroinvertebrates, plankton and fish. Scientists have been sampling these along the Coorong to determine the quantity and quality of potential food items.
What we have done so far?
Key developments and findings from investigations so far include:
- Evidence for strong regional variations in the availability of potential food resources to support waterbird and fish populations.
- A confirmed decline in the number of species of macroinvertebrate and fish species from north to south in the Coorong in relation to rising salinity.
- The total abundance of small-bodied fish was well below the long-term average.
- The energy content of potential food items for birds and fish is higher at the Murray Mouth and in the North Lagoon than in the South Lagoon.
The research will be used in modelling to inform the short and long-term management options currently being investigated to improve the health of the Coorong.