Optimising environmental conditions for nursery culture of juvenile Greenshell™ mussels (Perna canaliculus)

Abstract

The nursery culture of early juvenile bivalves is costly, requiring the provision of optimal environmental conditions for efficient production. Nursery production of mussels is particularly challenging because of their innate secondary settlement behaviour which can be triggered by unfavourable environmental conditions, resulting in mass migration of juveniles off aquaculture structures. This is a pronounced problem for the aquaculture of the Greeenshell™ mussel (Perna canaliculus) where losses of over 80% of juveniles are typical. Consequently, we examined the growth, survival and retention of juvenile mussels of this species in relation to four key environmental conditions (i.e., photoperiod, aeration, water flow, and oxygen levels) over 25 days in nursery holding conditions. Maintaining vigorous aeration and high dissolved oxygen (100%) both resulted in higher growth (126.1 and 89% respectively), survival (92.5 and 89% respectively) and retention (97.7 and 83.8% respectively). In contrast, photoperiod had minimal effect on juvenile mussel performance. This study suggests that providing suitable key environmental conditions has the potential to greatly improve the efficiency of production of P. canaliculus during commercial nursery aquaculture production.