2022 Early Hearing Detection & Intervention Virtual Conference
March 13 - 15, 2022
5/26/2021 | 8:30 AM - 10:30 AM | RISKS TO FISH POPULATIONS IN AUSTRALIAN DRYLAND RIVERS FROM THE COMBINED THREATS OF DROUGHT AND LOSS OF CONNECTIVITY | Virtual Platform
RISKS TO FISH POPULATIONS IN AUSTRALIAN DRYLAND RIVERS FROM THE COMBINED THREATS OF DROUGHT AND LOSS OF CONNECTIVITY
Flow intermittency subjects fish populations to frequent drought disturbance. Their population viability depends on waterhole refuges for individuals to survive drought (resistance) and recolonisation by recruitment and dispersal once flow returns (resilience). We combined remote-sensed mapping of waterholes that lasted through extreme drought in the northern Murray Darling Basin, Australia, with assessment of the impacts of in-stream barriers on limiting opportunities for fish to move after drought.
At peak drought, waterholes were few and generally small – representing only 11% of the total channel network. Most instream structures were small (mean 3 m height) but reduced fish movement opportunities on average by 87% and up to 100%. This large impact is a consequence of flow intermittency and is likely to reduce the capacity of depleted regional fish populations to recover after drought.
Combining information on risks from limited refuge habitat during drought and reduced movement opportunity following drought identified river segments where drought poses the greatest risk to local fish population viability.
This approach, considering resistance and resilience processes, is transferable to assessing and prioritising the management of drought and barrier risks to fish population viability in any non-perennial river setting.
- Dry rivers
- Non-perennial rivers
- Climate variability
Presentation:
This presentation has not yet been uploaded.
Handouts:
Handout is not Available
Transcripts:
CART transcripts are NOT YET available, but will be posted shortly after the conference
Presenters/Authors
Jonathan Marshall
(), Queensland Department of Environment and Science, jonathan.marshall@des.qld.gov.au;
ASHA DISCLOSURE:
Financial -
Nonfinancial -
Jaye Lobegeiger
(), Department of Environment and Science, jaye.lobegeiger@des.qld.gov.au;
ASHA DISCLOSURE:
Financial -
Nonfinancial -
Alisa Starkey
(), Ozius Pty Ltd, alisa.starkey@ozius.com.au;
ASHA DISCLOSURE:
Financial -
Nonfinancial -
Kate Hodges
(), Department of Environment and Science, kate.hodges@des.qld.gov.au;
ASHA DISCLOSURE:
Financial -
Nonfinancial -