Strategic R & D plan
This application fits within the Salmon Aquaculture Subprogram.
Reason for need
Currently, variable and unpredictable egg production has a potential opportunity cost for the Tasmanian salmon industry of $15-20 million per annum. Solving this problem is essential for the industry to maintain its continued strong commercial performance; however, the capacity to reach that solution is currently hindered by our limited understanding of the processes that regulate egg shell assembly and how these contribute to chorion and egg abnormalities, and also how these processes change with stock age and rearing temperature. This application addresses the need to overcome that knowledge gap. Industry results to date show that egg survival can be increased through thermal management; however, the relationship between stock age (maidens or repeats) and thermal conditions have not been systematically investigated, and the industry management protocols are essentially informed guess work.
The economic viability of sea cage farming of Atlantic salmon is strongly influenced by the cost of production of smolts. Understanding the mechanisms that contribute to, or cause reproductive failure in spawning fish is an essential component of reducing those industry production costs, and at a broader level, ensuring that there are sufficient smolts produced each year to maintain industry production. The issue has been identified as an industry priority with the stated SALTAS aim of reducing the reliance on repeat spawning fish for egg production. The potential cost of failing to solve the problem is high. The survival of eggs to the eyed embryo stage can be as low as 30-50%, compared with 80% for eggs from best performing fish (SALTAS data). Modelling of this cost gives direct increases in smolt production costs of $225,000 per annum, but a potential industry shortfall in production terms of $15-20 million per annum.