Effects of Willow (Salix spp.) Removal on Freshwater Ecosystem Dynamics: Spring and Autumn Monitoring 2009/2010

"July 2010".

Project Number: Monitoring the effects of Willow removal - M/BUS/274 (Related to Development of a Willow Removal monitoring program - M/BUS/115).

MDFRC item.

98 pages. 1 of 3 reports associated with project see (Effects of Willow (Salix spp.) Removal on Freshwater Ecosystem Dynamics. Autumn/Spring Monitoring 2007 & 2008) and (Effects of Willow (Salix spp.) Removal on Freshwater Ecosystem Dynamics: New Monitoring Sites).

In March 2006, The Murray-Darling Freshwater Research Centre (MDFRC) was commissioned and funded by the North East Catchment Management Authority (NECMA) to develop a literature review and a long-term monitoring program detailing the effects of willow removal on freshwater aquatic systems and to monitor these effects. The literature review was completed in June 2006 (Zukowski and Gawne 2006). This review demonstrated that although anecdotal evidence suggests an overall increase in ‘stream health’ in the long-term following willow removal, there is a consistent lack of data describing the effects of willows and willow removal on Australian aquatic environments. This made accurate predictions about short and long-term effects of willow removal difficult and led to the next phase of the project that identified key issues and recommended a monitoring program. The monitoring and key issues report developed a protocol for identifying key issues and a monitoring program associated with potential long-term effects of willow removal on aquatic systems (Zukowski et al. 2007). These key issues were based on the knowledge available and their importance to stream ecology. The next phase of the project was the implementation of the monitoring program at willow removal and control sites to ascertain the key long-term effects of willow removal on aquatic systems. Willow removal was undertaken in sites along a 600 m reach of Little Snowy Creek, Eskdale, Victoria, during April 2007. Monitoring was undertaken before (March 2007), one week (May 2007) and six months (October 2007) after willow removal in control and willow removal sites along Little Snowy Creek. A report outlining the first years monitoring results was produced in November 2007 (Zukowski et al. 2007). Monitoring was continued and undertaken bi-annually: one year (May 2008) and one and a half years (October 2008) after willow removal in control and willow removal sites along Little Snowy Creek. In July 2009 consultation between MDFRC and NECMA determined that four new sites would be added to the program. These sites were placed upstream of the existing monitoring sites on Little Snowy Creek and included a new willow removal site (pre-removal), a control site and two sites with a native vegetation riparian zone. This report summarises the literature review, key issue assessments and monitoring outcomes for the spring and autumn seasons of 2009 and 2010, now three years post willow removal at the first site near Eskdale.