Oral Presentation Australian Freshwater Sciences Society Conference 2022

Post-wildfire response of the native fish, Mountain galaxias (Galaxias olidus) in the Australian Capital Territory (#89)

Chris Malam 1 , Isobel Booksmythe 1 , Matthew Beitzel 1 , Lisa Evans 1 , Danswell Starrs 1
  1. ACT Government, DICKSON, ACT, Australia

Prescribed fire is an important land management tool applied in Namadgi National Park, while wildfire represents a significant threat to a range of aquatic and riparian values. A monitoring program for the small native fish, the Mountain galaxias (Galaxias olidus) was established in 2018 to inform fire management activities in the Upper Naas River catchment of Namadgi National Park. The Mountain galaxias is the only fish species to occur in this system. Following the devastating Orroral Valley wildfire in 2020, monitoring of Mountain galaxias was resumed to examine population responses post-wildfire. Monitoring is conducted in Autumn with bait traps used to capture fish, and a range of water quality and riparian habitat-related variables collected to examine how both aquatic and riparian habitat have responded to the fire, as well as examining the fish population response. Recruitment (defined as the proportion of captured fish < 50mm total length) appears to be reduced post-wildfire compared to pre-wildfire and when compared to non-fire impacted sites. This effect has extended into Autumn 2022, indicating that the post-fire impacts may be relatively long-lasting in this population. This presentation will outline future research priorities as well as efforts to incorporate a citizen-science component to the monitoring program.