1. Reality: Defined by Perception or Fact Joseph K. Buttner Department of Biology and Northeastern Massachusetts Aquaculture Center Salem State College Salem, MA 01970

2. Efficacy of Atlantic Salmon (Salmo salar) Culture Which is more energetically efficient, production of wild salmon in nature or culture of salmon?

3. Feed Conversion (food ingested/gain in fish) Wild salmon Classical Ecology10% efficient Piscivore 10-40%efficient FC (40% efficient)2.5:1 Cultured salmon Average FC1.2:1 Incomplete, must account for water content

4. Feed Conversion (water correction) Wild salmon (FC = 2.5:1, wet wt) Fish are 70-80% water75% water 2.5 (100%-75%) / 100 : 1 (100% -75%) / 100 = 0.625 : 0.25 FC (dry wt)2.5:1 Cultured salmon (FC = 1.2:1, wet wt) Prepared feed is <10% water 1.2 (100%-10%) / 100 : 1 (100%-75%) / 100 = 1.08 : 0.25 FC (dry wt)4.3:1 Incomplete, must account for protein content

5. Feed Conversion (protein correction) Wild salmon (FC = 2.5:1, dry basis) Fish are 80% protein on dry wt basis 2.5 (80%) / 100 : 1 (80%) / 100 = 2.0 : 0.8 FC (protein, dry wt)2.5:1 Cultured salmon (FC = 4.3:1, dry basis) Commercial ration 44-56% 50% protein 4.3 (50%) / 100 : 1 (80%) / 100 = 2.15 : 0.8 FC (protein, dry wt)2.7:1 Incomplete, must account for protein as fish meal

6. Feed Conversion (fish meal correction) Wild salmon (FC = 2.5:1, dry basis-protein) Fish meal 100% protein 2.5 (100%) / 100 : 1 (100%) / 100 = 2.5:1 Cultured salmon (FC = 2.7:1, dry basis-protein) Ration is 25-35% fish meal 30% Fish meal 70% protein Fish meal 10% water (30%) (70%) (90%) = 19% 2.7 (19%) / 100 : 1 (100%) / 100 = 0.5:1

7. So What? FC in cultured salmon is 5x more efficient than wild salmon Problem perceived as a biological shortcoming is a societal challenge Sociological response is needed to shift consumer preference to herbivorous or omnivorous species Factual information is pre-requisite for “constructive dialogue and effective collaboration”