01 Sep Janice Kerr
Janice Kerr, Australia
Janice Kerr has been working in the field of aquatic ecology for 15 years and has most recently been working with the Queensland Department of Natural Resources and Mines in Toowoomba to deliver amongst other things the Environmental Flows Assessment Program. This role provides technical knowledge on aquatic ecology that underpins the science requirements for Water Planning and supports the work of the Water Planning Ecology Group at DSITI. Her recent projects have concerned stable low-flow spawning fish, floodplain wetlands and barriers to fish movement. Previously, much of her work was in the field of river and wetland biogeochemistry, including seven years with the Murray-Darling Freshwater Research Centre in Albury-Wodonga, a PhD with La Trobe University and a post-doctoral position with the University of Queensland.
Presentation Title: Stable low-flow spawning fish habitat assessments: Calculating flow thresholds to inform the Environmental Assessment of state Water Plans (Qld)
EcoModeller is used by the Queensland government to assess the risks to aquatic species from current and proposed water resource use. This model includes various “plug-ins” that calculate the frequency of defined flow conditions at nodes within Water Plan areas. The Stable Low-Flow Spawning Fish (SLFSF) plug-in is used to model spawning opportunities for SLFSF. Further data processing provides an indication of the risks posed to SLFSF from each modelled flow regime. In Phase 1 of this project, we adapted this model for use in the Condamine-Balonne, Moonie and Border Rivers Water Plan areas and identified the parameters that limited our confidence. These parameters were the low-flow threshold (optimal discharge to create suitable flow conditions) and the daily change in water level. In Phase 2, we characterised spawning habitat near selected model nodes, including the depth and distribution of spawning substrates, the water velocity and the channel cross-section. This node specific knowledge was used to firstly relate discharge at habitat sites to discharge at a nearby gauge, and secondly to refine the conceptual model relating flows and spawning in selected species. The refined conceptualisation highlighted the importance of water turbidity and the presence of submerged macrophytes in defining low-flow thresholds and daily water level change suitable for egg and larval development. The SLFSF EcoModeller “plug-in” was then modified to provide additional options for stipulating these parameters or using the default values. Outcomes of this work are currently being used in the Environmental Assessment of the Condamine-Balonne and Border Rivers Water Plans. The enhanced understanding of SLFSF habitat characteristics in these catchments will inform future Environmental Flow Objectives, Ecological Objectives and ecohydraulic rules. Knowledge gained in these projects was used to provide advice to the Commonwealth Environmental Water Office regarding environmental watering actions to support SLFSF in the Dumaresq River.