A comparison of the technical efficiency

A comparison of the technical efficiency of Aquaculture Stewardship Council certified shrimp farms to non-certified farms

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The Aquaculture Stewardship Council’s shrimp certification standard is meant to serve as a market-based tool that rewards the better actors in the industry for improved performance in areas like technical efficiency, social responsibility, and traceability. The goal of this study was to compare production methodology and efficiency of farms currently certified to the ASC shrimp standard to non-certified farms from recent field surveys in the same geographical areas.

The data revealed how difficult it has been for the ASC shrimp standard to capture a meaningful share of the global shrimp market. These findings were used to make recommendations for the ASC standard and certification standards in general, including a greater emphasis on requirements for limits on efficiency-based metrics beyond reporting the outcome of the calculation.

One of the most valuable seafood commodities is farmed penaeid shrimp, which has a value that far exceeds the proportion of tonnage produced. The whiteleg shrimp, Litopenaeus vannamei, is the most commonly cultured penaeid species globally, accounting for 83% of all penaeid shrimp culture.

Socially, shrimp farming has been criticized for exploiting local labor and disconnecting local com- munities from natural resources and has been more recently linked to allegations of forced labor on fishing vessels used for the production of fishmeal in shrimp feeds.

A comparison of the technical efficiency

Nevertheless, shrimp trawling has also caused damage to marine ecosystems. The ills of shrimp aquaculture can be greatly reduced by better farm siting and operations, while those of trawling are more difficult to correct, and the penaeid shrimp catch has plateaued.

The interest in promoting sustainability in aquaculture and developing best management practices is generally shared amongst environmentalists, industry, and academic institutions.

The role of certification schemes is to allow consumers to discern shrimp from well operated shrimp farms from those originating from poorly operated farms and thereby encourage sustainable practices with their purchases.

“The concept behind certification schemes is that by setting high standards for certification, better actors in the market will be rewarded with better prices and preferential treatment from buyers.”

Over time, certification will theoretically lead to a shift in performance, towards better performance, there by improving the standard practices of the industry. However, the practice of certification has not existed long enough to demonstrate this pattern.

The Aquaculture Stewardship

Council (ASC) is one of the world’s most prominent certification bodies in aquaculture. They have several standards for the certification of common aquaculture products, including the Aquaculture Stewardship Council shrimp standard.

A comparison of the technical efficiency

Originally crafted in 2015, it includes standards that must be met by a farm for worker’s welfare, community engagement, resource efficiency, and environmental responsibility. The objective of this study was two fold:

  • i. describes the characteristics of the farms certified under the ASC shrimp standard,
  • ii. compare quantitative efficiency metrics from farms certified by the ASC shrimp standard to data recently collected in Southeast Asia, and Ecuador with field surveys at shrimp farms.

Methods y Results

Data from the ASC’s publicly available certification audits were extracted to create the data for this study. The audits were screened for data in September and October of 2020. The following variables were compared: average farm size, production, production intensity, FCR, water exchange rate, and energy use.

“Altogether, there were 123 farm audits that strictly culture L. vannamei in the ASC auditing data during the time of data screening, with most of the farms occurring in Asia.”

The Latin American countries, where there are certified farms, have a relatively high percentage of production covered from certification, ranging from 3.26% in Mexico to 94.56% in Honduras. The countries from Asia where farms are certified have far less production under certification.

Altogether, 4.14% of global production of L. vannamei is certified under the ASC standard. Based on data in the audit reports, Ecuador has the most area of land under certification with over 22,000 ha certified, roughly 45% of the total land for L. vannamei farms certified under the ASC Shrimp standard.

The countries with the most certified farms were India (36), Ecuador (27), and Thailand (25). ASC farms were significantly larger than the noncertified counter- parts as revealed from recent data obtained from field surveys, with the ASC farms in Asia being 10 times larger on average than non-certified farms.

A comparison of the technical efficiency

Production intensities were predictably higher in Asia than Latin America, but certified farms in Asia on average had the highest production intensity of all groups. Water exchange as a percentage of daily pond volume was significantly lower at farms in Asia that were certified than uncertified farms.

Both Asian and Latin American farms that were certified used less energy than their uncertified counterparts, although the difference was not significant in Latin America.

“There was a significant difference in the rate at which farms reported the use of fertilizer, Zeolite, and Probiotics in Asia farms.”

In all three cases, the non-ASC farms had a higher rate of reporting chemical use for these chemicals. In all cases except disinfectants, ASC farms reported using these chemicals at a lower proportion than their non-certified counterparts.


The ASC’s shrimp standard, developed through a multi-stakeholder process, is meant to be at the leading front of certifications in the aquaculture sector.

One of the most apparent conclusions from this data is that there are truly two different predominant styles of shrimp farming that have been able to obtain certification.

“For the most part in Asia, the farms are highly intensive and with small ponds and a comparably small overall area when compared to ASC farms elsewhere, while the farms in Latin America are large and semi-intensive.”

Based on the size of the farms that are being certified, it is clear that the farms that are able to obtain certification are only those that are either large enough or are producing enough volume in smaller highly intensive farms to absorb the costs of certification, which is understood to be substantial.

This creates a paradoxical problem for the ASC, which is in order to broaden the market share of the standard and therefore its potential impact, the standard would likely have to be altered in order to be obtainable for a larger number of farms.

A comparison of the technical efficiency

Several certifications in this study were multi-site (roughly 25%), so this does seem to be a path to certification for clusters of smaller farms.

The ASC standard has rather strict limits on amounts of phosphorus and nitrogen that may be discharged per ton of shrimp harvested. While compliance with these limits requires better management, these limits do not assure water quality protection in receiving water bodies.

“Unless the assimilation capacity of the receiving water body is known, a farm can comply with the ASC nitrogen and phosphorus standards but release enough nitrogen and phosphorus to initiate or exacerbate eutrophication.”

The FCR and by extension type and amount of feed used by a farm largely determines its environmental impact, as feed management plays a role in the amount of embodied resources tied up in production in the farm, the water quality outcomes, the impacts on wild fish, and the health of shrimp in ponds.

The worst performing group in this study was the ASC-certified farms in Latin America, and the best performing group was the ASC-certified farms in Asia.

It is likely that the large size of the ponds in Latin America, indicative to the production systems in this region, limit the ability to manage feed inputs and production. Large ponds are more difficult to manage intensively compared to relatively small ponds.

A comparison of the technical efficiency

Direct energy use is an important measure, as it relates to the use of aeration and pumping on a farm, which are key management practices that can determine the environmental impacts of the farm. ASC farms were better on average than their noncertified peers in both Asia and Latin America, which is encouraging for an eco-label.

Chlorination with bleach (NaOCl) and high test hypochlorite [Ca(OCl)2] were by far the most common method of chlorination. Disinfection of ponds also eradicates wild fish, so the use of piscicides such as rotenone and saponins was not common in Asia.

The main therapeutic applied were organic acids such as lactic or ascetic acid which are used to prevent Vibrio infections in shrimp. None of the ASC farms in Asia used therapeutic, and therapeutic use in Latin America was more common at non-ASC farms.

“The greatest use of vitamins at non-ASC farms in Asia, and Vitamin C was the common one applied.”

The most critical pieces of information missing from several of the audits that should be specified to be explicitly included are the actual production of the farm for the most recent complete year, the number of production ponds (and nursery and hatchery ponds separately), the different water surface areas such as the production ponds, canals, and reservoirs if any are present, and the total area of the property and the area dedicated to shrimp farming in the cases where not all of the property is utilized.


The ASC appears to have captured the high end of the market in terms of farm size, suggesting that large, in many cases corporate, farms are the farms that are able to obtain certification. There appears to be a dichotomy between Latin America and Asia in terms of farm style and management, although this was relatively well known.

Finally, while technical efficiency is an important aspect of sustainability and was the focus of this study, this study does not capture the entirety of what the ASC certification is meant to assess, including other important aspects of responsible farming such as fair labor practices, supply chain traceability, community engagement, previous land use at the farm site, and local regulation compliance.

Periodic comparisons of ASC certification data to industry surveys will strengthen the claims made by the ASC mainly that they are a leader in environmental stewardship in aquaculture.

This is a summarized version developed by the editorial team of Aquaculture Magazine based on the review article titled “A COMPARISON OF THE TECHNICAL EFFICIENCY OF AQUACULTURE STEWARDSHIP COUNCIL CERTIFIED SHRIMP FARMS TO NON-CERTIFIED FARMS” developed by: ROBERT P. DAVIS – Auburn University, CLAUDE E. BOYD – Auburn University.
The original article was published on JULIO de 2021 through ELSEVIER under the use of a creative commons open access license.
The full version can be accessed freely online through this link: https://doi.org/10.1016/j.crsust.2021.100069.

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