Poster Presentation Australian Marine Sciences Association 2025 Conference

The Effect of Microbial Concentration on Early Life History Stages of Ecklonia radiata. (#125)

Lachlan Burns 1 , Lewis Hurley 1 , Fiona McQueen 1 , Ryan Hesse 1 , Emma Kerr 1 , Elizabeth Dinsdale 1 , Georgina Wood 1
  1. Flinders University, Adelaide, South Australia, Australia

Global kelp populations are decreasing at alarming rates due to anthropogenic stressors, emphasising the need for scalable restoration efforts. To meet the demand, kelp sporophyte cultures have been grown in mass using sterile tanks, however transplantation of sterile cultures has been largely unsuccessful. It’s hypothesised the sterile environment hindered the success of translocation, as sporophytes lacked exposure to environmental bacteria and viruses. Absence of immunity may inhibit the establishment of juvenile sporophytes. We will test the effect of microbial exposure on the early life stages of Ecklonia radiata, the dominant kelp species in Australia’s temperate waters. Tangential flow filtration will be used at two Adelaide beaches, Second Valley and Port Noarlunga, to separate the microbes into concentrations. The microbial concentrations will create 4 environmental categories: sterile, low, environmental, and high. Flow cytometry will determine the bacterial and viral abundance and gametophyte recruitment and sporophyte development will be recorded over a 12-week period. We expect to see greater recruitment and development in intermediate to environmental conditions, with sterile and high concentrations showing a decrease.