MWRPP Report 15.7: Cockatoo Swamp Vegetation Condition Monitoring Program: baseline data.

The Yellingbo Nature Conservation Reserve hosts critical habitat for the endangered Helmeted Honeyeater and lowland Leadbeater's Possum, species associated with Eucalyptus camphora woodland and shrub thickets. The Cockatoo Swamp area within the reserve faces threats from inappropriate water regimes, prompting Melbourne Water to plan capital works in 2016. These works aim to reinstate natural wetting and drying patterns by installing a drainage pipe and removing sections of upstream levee.To assess the impact of these interventions, a monitoring program using a Before-After-Reference-Impact (BARI) design has been established across six sites. The program will track tree condition, seed production, seedling recruitment, and vegetation composition. Baseline data collected in April-May 2015 revealed poor tree condition and low seedfall rates in dieback-affected areas, while areas behind levees lack suitable habitat structure for the target species. Reference sites showed better tree condition but negligible woody plant recruitment.The restoration project aims to improve drainage in dieback areas, potentially enhancing tree condition, and promote woody plant recruitment in disconnected areas through levee removal. However, low recruitment rates in reference sites suggest additional challenges such as competition and browsing may persist.Annual surveys are planned for early autumn, with at least three years of post-works monitoring required to assess trends accurately. The results will inform habitat suitability for the Helmeted Honeyeaters and Leadbeater's Possums, supporting ongoing conservation efforts in this crucial wetland forest ecosystem.