Aerator energy use in shrimp farming and means for improvement

Aquaculture Fish & Fisheries

McNevin

2021

Self Cite

The purpose of this study was to assess the amounts of land, water, energy in fuels, and wild fish for fishmeal and fish oil in feeds required per tonne of harvested, farmed shrimp in five countries producing most of the shrimp destined for the international market. Land use for whiteleg shrimp Litopenaeus vannamei production differed slightly between Indonesia (0.37 ha/t shrimp) and the other four, major shrimp exporting countries -Ecuador, India, Thailand, and Vietnam (0.42-0.46 ha/t shrimp). Total water use was greater in Ecuador (76,800 m 3 /t) and Indonesia (55,000 m 3 /t) than in the other three countries (14,000-45,500 m 3 /t), but most water was saline. Freshwater use was mainly embodied in feed, did not differ among countries, and averaged 6.3% of total water use. Energy use ranged from 56.0 GJ/t (Ecuador) to 98.8 GJ/t (Thailand). All Asian countries had energy use above 75 GJ/t. Wild fish use for fishmeal and fish oil in feeds was greatest in Ecuador (0.891 t/t) and similar in Asian countries (0.612-0.670 t/t).In terms of edible crude protein, whiteleg shrimp was similar to broiler chickens, but more efficient than pigs and beef cattle in land and freshwater use, but greater in energy use than were the three terrestrial meat sources. Compared to L. vannamei, black tiger shrimp Penaeus monodon required more land, a greater amount of water, but less energy per tonne of shrimp. Although comparatively small differences in average uses of these primary resources were found among countries, the large variation which was noted among farms in each country suggests that resource use could be improved considerably.

Section: Average Area Of Individual Production Ponds Was Much Greater Insupporting

confidence: 90%

Comparison of resource use for farmed shrimp in Ecuador, India, Indonesia, Thailand, and Vietnam

Aquaculture Fish & Fisheries

McNevin

2021

Self Cite

“…The main technique for increasing production obviously would be greater use of mechanical aeration. The increase in yield possible with mechanical aeration is dependent on the amount of aeration applied, because aerators have the capacity to allow 300-500 by more shrimp per horsepower (Boyd & McNevin, 2020). Aeration generally does not increase the energy input per ton of shrimp, but allows greater shrimp yield in proportion to the amount of aeration applied.…”

Section: Discussionmentioning

confidence: 99%

Resource use in whiteleg shrimp Litopenaeus vannamei farming in Ecuador

J World Aquaculture Soc

Wilson³

et al. 2021

Self Cite

A survey of 101 shrimp farms in Ecuador revealed that the average annual shrimp yield based on production pond water surface area was 7.03 ± 0.93 (SE) t/ha/year. The range in annual yield among the five provinces with shrimp farms was 3.67 ± 0.71 to 11.95 ± 5.56 t/ha year, respectively. Averages for total land, water, and energy use were 0.54 ± 0.01 ha/t shrimp, 76,817 ± 6,330 m3/t shrimp, and 61.2 ± 4.2 GJ/t shrimp, respectively. Average wild fish use for fish meal and fish oil included in feed was 0.65 ± 0.02 t/t shrimp. One‐fourth of land use was land embodied in feed. Nearly 80% of total water use was incurred for exchanging water. Eighty‐seven of the farms practiced daily water exchange at an average rate of 8.5% pond volume per day (range 0.7–30%). Pumping water at all farms and mechanical aeration at 47 of the farms were the major direct energy uses. About half of the total energy use was embodied, and roughly half of the embodied energy was in feed.

“…The dissolved oxygen limit on pond yield intensities in semi-intensive culture is overcome in intensive culture by applying mechanical aeration. This practice increases the availability of dissolved oxygen allowing pond yield intensity to increase in relation to the aeration capacity installed in a pond (Boyd & McNevin, 2020).…”

Section: Limiting Factors For Intensificationmentioning

confidence: 99%

“…With the types of aerators currently available, the general rule is that each 1 hp of installed aerator capacity will support an additional 0.5 t of shrimp. Most shrimp farmers apply somewhat more aeration that this, often 1 hp for each 0.35-0.40 t of shrimp (Boyd & McNevin, 2020). While the amount of installed aeration capacity often is estimated from the production objective (t ha À1 crop À1 ) using the aeration horsepower:shrimp biomass ratio mentioned above, the relationship between aeration rate and yield usually is not linear.…”

Section: Importance Of Dissolved Oxygenmentioning

confidence: 99%

“…While the amount of installed aeration capacity often is estimated from the production objective (t ha À1 crop À1 ) using the aeration horsepower:shrimp biomass ratio mentioned above, the relationship between aeration rate and yield usually is not linear. At greater yield intensity, more installed aeration capacity usually is necessary per ton of shrimp and especially in biofloc systems (Boyd & McNevin, 2020).…”

Section: Importance Of Dissolved Oxygenmentioning

confidence: 99%

See 1 more Smart Citation

Perspectives on the mangrove conundrum, land use, and benefits of yield intensification in farmed shrimp production: A review

J World Aquaculture Soc

McNevin

2021

Self Cite

Globally, shrimp farms occupied an estimated 3.490 million hectares (Mha) of land and operated 2.426 Mha of production ponds in 2018. Extensive shrimp farms used 1.804 Mha of farm area (1.377 Mha of production ponds), but produced 11.4% of global shrimp production. An estimated 1.718 Mha of land was required to produce ingredients for feeds used in semi-intensive and intensive shrimp farming, bringing total land use to 5.160 Mha. Extensive production is located in the intertidal zone and much of this land formerly was or still is in mangrove areas. Expansion of shrimp farms into mangrove areas has slowed. Mangrove areas are inferior sites for shrimp farms, and governments have imposed stricter regulations to protect mangroves. Shrimp farming in mangrove areas is unnecessary to supply the global shrimp demand. Scenarios for increasing global shrimp production without further increase in shrimp farm area are presented. But, if the demand for shrimp continues to increase, it will be impossible to freeze the total land footprint for farmed shrimp, because the land needed for feed presently is roughly equal to the direct land use for shrimp farms. Direct land use for farms can be frozen through greater production pond yields.