Standard Presentation (15 mins) Australian Marine Sciences Association 2022

Seasonal reproduction of the kelp species Lessonia corrugata (#205)

Allyson Nardelli 1 , Wouter Visch 1 , Glenn Farrington 1 , Craig Sanderson 2 , Alecia Bellgrove 3 , Jeff Wright 1 , Catriona Hurd 1
  1. Institute for Marine and Antarctic Studies | UTAS, Kingston Beach, TASMANIA, Australia
  2. Tassal Pty Ltd, Hobart
  3. Deakin University, Warrnambool VIC

Lessonia corrugata is found in wave-exposed and moderately wave-exposed environments and recently of commercial interest. However, knowledge about fundamental biology is lacking. Here, we studied the seasonal reproduction of L. corrugata at three sites with different wave exposition levels in Tasmania. Seasonal reproduction was assessed by % fertile blade tissue and classified into four maturation stages. Zoospore viability was evaluated by the number of released, size and swimming time. We found that L. corrugata was reproductive all seasons except spring. Winter had more mature tissue, and it varied between exposed sites (>70%) and sheltered sites (<50%). The number of zoospores released in winter was higher than in other seasons,  with a more expressive number for a more exposed site than a sheltered site. Furthermore, we observed moving zoospores 52h after release. Zoospores released in autumn swam longer compared to winter, but 50% of zoospores stopped moving after 8h. Finally, we found a positive correlation between swimming time and zoospores size. In conclusion, L. corrugata was found to be a seasonal anticipator for reproduction, which was also found to be mediated by wave exposure. The results found here can assist in developing a L. corrugata aquaculture industry in Tasmania.