Traditional Gamilaaraay Language of the Gomeroi Nation used in this article (H. White & B. Duncan – Speaking Our Way, M. Mckemey).

The Commonwealth Environmental Water Holder’s (CEWH) Science Program funds the Flow Monitoring, Evaluation and Research (Flow–MER).

Written by Tamara Kermode.

Figure 1 Moree Airport (BOM station - 053115) rainfall for 2022-23 water year compared to the long-term average.

Conditions throughout the 2022-23 water year (July 2022 – June 2023) were relatively wet. Rainfall within the Guwayda (Gwydir) River Selected Area was at or above average for several months, particularly August to October (Figure 1). For the second year running, significant inundation was observed throughout the Lower Guwayda catchment, with over 226,000 ha of floodplain, wetlands and river channels inundated in October 2022.

Deliveries of water for the environment were made to the Carole, Gingham, Lower Guwayda and Mallowa channels. A total of 3,332 ML of both NSW and Commonwealth

water for the environment was delivered down the Lower Guwayda channel into the wetlands from mid-December 2022 to late March 2023 to support colonial waterbird breeding (Figure 2), along with a further 5,617 ML directed down the Gingham channel and into the watercourse for the same purpose. Within the Lower Guwayda and Gingham systems an estimated 60,000 nests were recorded comprised mainly of egrets, dhaarrin (nankeen night herons, Nycticorax caledonicus) and yuwagayrr (ibis, Threskiornithinae).

Figure 2 Felix Noble and David Preston conducting colonial waterbird breeding surveys in the Lower Guwayda in March 2023. Photo credit Tamara Kermode.

Warrambool (wetland) vegetation continued to respond favourably to the wet conditions, with most communities surveyed remaining in or transitioning to a wet-phase state, dominated by amphibious plant species (Figure 3). In the Lower Guwayda Warrambools, the marsh club-rush wetland threatened ecological community was observed to be in good condition.

Despite the wetter conditions over the last few years, native fish communities remained in poor health. The river systems have continued to be dominated by exotic species and native fish recruitment was low (Figure 4). Providing connection flows to warrambool areas to allow the fish to move back up the channel system would aid in the longevity of native fish populations in the future.

Figure 3 David Mackay looking out over the vegetation of the Lower Guwayda during vegetation surveys. Photo credit UNE.
Figure 4 Juvenile Murray cod (Maccullochella peelii) caught during surveys in the Lower Guwayda early 2023. Photo credit DPI Fisheries.

Managing water for the environment is a collective and collaborative effort, working in partnership with communities, private landholders, scientists and government agencies – these contributions are gratefully acknowledged.

We acknowledge the Traditional Owners of the land on which we live, work and play. We also pay our respects to Elders past, present and emerging.