Addressing Natural Resource Use Efficiency in Aquaculture Certification

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1 Addressing Natural Resource Use Efficiency in Aquaculture Certification Claude E. Boyd School of Fisheries, Aquacultures and Aquatic Sciences Auburn University, Auburn, Alabama USA

2 Brief History of Responsible Aquaculture Movement 1960s-1980s Aquaculture considered to be the blue-revolution. 1990s Environmental NGOs became concerned over environmental effects of aquaculture. Aquaculture responded with voluntary environmental programs that were not verifiable Certification programs were developed present Certification is becoming quite common.

3 Concerns about Certification There are many standards with no weighing of the importance of each. Some of the standards tend to be ill-chosen. The benefits on the environment are assumed not verified by investigation. Difficulty of compliances varies among programs. The auditors cannot check environmental impacts reliably records are about the only verifiable aspect. Producers complain of costs.

4 Resource Use Efficiency Most negative environmental impacts result from resource use. Improving efficiency at the farm-level lessens resource use and associated impacts per unit production, i.e., improving FCR lessens feed use and feeding waste. Improving efficiency also lessens embodied resource use and associated impacts, i.e., better FCR, less feed, land, water, energy, and wildfish use for feed ingredients and manufacturing.

5 Embodied land and water in feed. Species Land (ha/t) Water (m 3 /t) Rainbow trout Atlantic salmon Ictalurid catfish ,227 Pangasius ,200 Black tiger shrimp ,130 Whiteleg shrimp ,116 Tilapia ,685

6 Embodied energy for feed. Species GJ/t) Ictalurid catfish 3.84 Pangasius 4.27 Tilapia 4.77 Whiteleg shrimp 8.01 Black tiger shrimp 9.42 Rainbow trout Atlantic salmon 11.42

7 Wildfish for feed. Species (kg/t) Ictalurid catfish 0 Tilapia 200 Pangasius 603 Whiteleg shrimp 818 Black tiger shrimp 1,302 Rainbow trout 2,299 Atlantic salmon 2,880

8 Effect of reducing FCR by 0.1 unit. Variable Whiteleg shrimp Tilapia Global feed-based production (t) 2,817,962 3,374,000 Savings: Feed (t) 281, ,000 Value (million $US) Embodied energy (GJ) 2,257,186 1,783,980 Embodied land (t) 70, ,700 Water (million m 3 ) Wildfish (t) 230,509 74,800

9 Comment For the six species discussed here, a global reduction in FCR of 0.1 would annually Reduce aquafeed use by 3.2% ( $800 million US). Conserve 1,398,376 barrels of oil equivalent (2.3 billion kw hr). Lessen land use in agriculture by 270,000 ha. Reduce freshwater use by 1.4 billion m 3. Conserve 1,240,000 kg of wildfish.

10 Effluent Water Quality Limits Will prevent high concentration of a pollutant protects mixing zone. Will not prevent a high load of a pollutant load is volume concentration. High load can exceed assimilation capacity of receiving water. Results of water quality monitoring to detect the health of a water body do not warn of approaching tipping point.

11 Alternative to Water Quality Limits FCR limit lowers waste load. Limits on N and especially P in feeds. A standard for amount of aeration enough to stimulate waste oxidation by avoiding low DO concentration. Limit on water exchange lengthens hydraulic retention time to favor waste assimilation in system.

12 Some trade-offs. Atlantic salmon to tilapia Less energy More land More water Less wildfish Black tiger shrimp to whiteleg shrimp Less energy Less land About same for water Less wildfish

13 Some Trade-offs with Feed Ingredients More plant ingredients more land, more water, less energy, less wildfish. More agricultural by-product ingredients less land, less water, less wildfish. Energy depends on type of by-product.

14 Other Suggestions Reduce use of amendments this will depend on farm site as in the case of liming. Improve aeration efficiency and operate aerators only as required less use early in crop and use more in the nighttime than in the daytime.

15 Other Suggestions Farms have a wide range of production procedures stocking rates, aeration rates, amount of water, liming rates, disinfectant rates, etc. There is no typical suite of farm inputs as many believe. Need more data to ascertain efficiency range in other countries and with other types of aquaculture. Need to promote more standardized practices across production sectors.