Dr Sarah Mika is a lover of water and the life that teems in its presence. From water quality to microinvertebrates to macroinvertebrates, Sarah is passionate about the small things that make wetlands boom. In this story Sarah tells of this passsion; how it started while studying and playing in the coastal rivers of NSW and how it’s fuelled now by researching various wetlands of the northern Murray-Darling Basin for the CEWO’s Flow-MER Project.
What is the first fish species that pops into your head when you think of the Murray-Darling Basin? I bet it’s the Murray cod, or Guduu in Gamilaraay language (pictured above). You might remember a family fishing trip and cod on the BBQ. Or maybe you have just seen pictures or film of Australia’s largest freshwater fish…
Water for the environment will complement recent natural flows to support the replenishment of channels and wetlands in the Gwydir valley between late spring and summer 2020-21. These flows aim to help native fish survival by providing access to refuge habitat and food, increase connectivity within the Gwydir system and improve water quality in pools.
The past five years have been challenging, to say the least, for many fish species within the Gwydir Valley, particularly regarding spawning and recruitment (aka. breeding). This has made the recent findings from the NSW Fisheries team all the more exciting. The team found that Murray cod and Freshwater catfish populations of the Gwydir Valley have had great breeding success in the past 12 months, demonstrating the resilience of both species during the ‘big dry’.
The National Parks and Wildlife Service (NPWS) is pleased to announce the reopening of the ‘Waterbird Lagoon’ at the Gwydir Wetlands State Conservation Area, near Moree. Check the website nationalparks.nsw.gov.au for the latest updates. Click here for the NPWS announcement – Gwydir Wetlands Waterbird Lagoon open days.
A key member of the team assessing and monitoring water for the environment in the Warrego and Gwydir systems, Steve contributes data on fauna that inhabit these areas. His observations in the Warrego and Gwydir described in this story indicate the importance of good flow, namely rainfall and water for the environment, in these dynamic wetland environments.
Native fish play an important role in the environment of the Murray Darling Basin. They also have a large social and cultural value to many Basin communities. How we use water in our rivers has changed their natural flow patterns and impacted native fish communities. Deciding how we use water for the environment can therefore provide major benefits to sustaining our native fish.
Lippia (Phyla canescens) is a significant weed in the Gwydir wetlands. It spreads along the ground smothering native grasses, reducing both our native habitat and our natural pastures for cattle. Water couch and lippia tend to live in the same areas. What we have found is that the delivery of environmental water can benefit water couch, allowing it to dramatically out compete the lippia weed.
To the west of Moree the land gets flat, very flat. So flat that the Gwydir River disperses into several channels and flow paths, forming the Gwydir wetlands. These wetlands support some of the largest breeding colonies of waterbirds in Australia and include areas that are listed as Wetlands of International Importance (Ramsar convention).
