October 7, 2021
Improving the management of Instream Woody Habitat in Victoria
In the past, some believed that instream woody habitat (IWH) increased risks of flooding and erosion and hampered river navigation.
This led to riparian clearing and the removal of large quantities of IWH in rivers throughout the world. In Australia, IWH was still being removed until the late 1980s.
The Arthur Rylah Institute undertook a long-term project to assess the importance of IWH for fish and river health. This included state-wide mapping of existing IWH and predictions of natural IWH over almost 27,770 km of rivers, and quantifying links between habitat and important fish populations to help guide IWH restoration.
In Victoria, it is estimated that on average IWH volumes were 41% lower than in pre-European times, with 30% of river reaches assessed to have reductions of >80%1,2 .
Such losses have caused increased flow velocities, channel enlargement, bed degradation and loss of important aquatic habitats. This has contributed to declines in river productivity and the health of aquatic ecosystems, including native fish.
Read more here: https://www.ari.vic.gov.au/research/rivers-and-estuaries/instream-woody-habitat
