Water Quality and Murray Cod: Temperature and Dissolved Oxygen in Pools of the Upper Murrumbidgee River

Fiona DYER, David Sangston, Alica Tschierchke, Danny Wright, Patrick ROSS-MAGEE, Alan COUCH, Mark LINTERMANS

    Research output: A Conference proceeding or a Chapter in BookConference contribution

    Abstract

    Dissolved oxygen (DO) concentrations and high temperatures are known to adversely affect fish populations in rivers. While thermal and oxygen stratification are rare under natural conditions in upland river systems significant reductions in flow caused by water abstraction, can result in low DO concentrations and high temperatures. The effects of flow and geomorphic character on DO concentrations and temperatures in pools were investigated between 2011 and 2014 in the upper Murrumbidgee River. Dissolved oxygen and temperature were recorded at hourly intervals in six pools ranging in depth from 3 to 7 m and known to provide important habitat for Murray cod. High water temperatures and low DO concentrations were observed at all sites and were most common between January and March. Antecedent air temperatures and the geomorphic character of the pools were important determinants of water temperatures. Deep pools in confined bedrock reaches displayed cooler water temperatures at depth and are likely to provide fish with refuge from high water temperatures. Such deep pools were most likely to experience persistent low DO conditions, particularly at depths beyond 4 m. Flows of up to 300 ML/day had little effect on the probability of low DO concentrations at depth which means that flow manipulation is unlikely to improve DO conditions at the deepest points of the river. There is sufficient variation in pool morphology along the river to provide fish with refuge from high temperatures and low DO conditions, however fish must be able to move to access suitable conditions
    Original languageEnglish
    Title of host publication11th International Symposium on Ecohydraulics 2016
    EditorsJ.A. Webb, W.M. Koster, I.G. Stewart, P Reich, M.J. Stewardson
    Place of PublicationAustralia
    PublisherEngineers Australia
    Pages1-7
    Number of pages7
    ISBN (Print)9780734053398
    Publication statusPublished - 2016
    Event11th International Symposium on Ecohydraulics 2016 - Melbourne, Melbourne, Australia
    Duration: 7 Feb 201612 Feb 2016
    http://ise2016.org/ (Conference website)

    Conference

    Conference11th International Symposium on Ecohydraulics 2016
    CountryAustralia
    CityMelbourne
    Period7/02/1612/02/16
    Internet address

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    Cite this

    DYER, F., Sangston, D., Tschierchke, A., Wright, D., ROSS-MAGEE, P., COUCH, A., & LINTERMANS, M. (2016). Water Quality and Murray Cod: Temperature and Dissolved Oxygen in Pools of the Upper Murrumbidgee River. In J. A. Webb, W. M. Koster, I. G. Stewart, P. Reich, & M. J. Stewardson (Eds.), 11th International Symposium on Ecohydraulics 2016 (pp. 1-7). Australia: Engineers Australia.