Shrimp farming advances, challenges, and opportunities

Abstract

We have seen a significant growth of the shrimp industry over the last decade. Total imports in 2022 were 3,248,338 ton (Van der Pijl, 2023), with additional production in China estimated at 1,487,501 ton (Fu-Chi, 2023). China and Vietnam in Asia (945,791 ton) and the US (837,622 ton) absorbed most of the growth in shrimp production. Ecuador has seen a compound annual growth rate (CAGR) of 17% from 2012 to 2019 and a very significant CAGR of 25% from 2020 to Q2 2023. Reported production by the National Aquaculture Chamber (CNA) in this country was 1,051,758 ton in 2022, with an expected 10% increase for 2023, equivalent to 1,158,460 ton. Similarly, the Indian Ministry of Commerce reported a CAGR of 19% from 2012 to 2019, reaching a peak of 734,160 tons. This has since been reduced to an expected export volume of 632,802 tons for 2023 (Van der Pijl, 2023) due to market oversupply.

Boyd and McNevin (2018) reported that from a total of 2.4 million ha available for shrimp farming worldwide, 1 million had an annual production of less than 300 ton/ha (0.3 million ton), and 1.4 million ha produced >300 ton/ha/year, equivalent to 5.2 million ton, representing 94% of production output from only 58% of production area. Commercial farming technologies vary significantly between regions. For example, semi-intensive production in Ecuador result in annual yields between 1–5 ton/ha/year, while the intensive systems in India produce 5–10 ton/ha/year. Reports of 10–25 ton/ha/year are the norm for Thailand's super-intensive systems, and 25–100 ton/ha/year would be expected in a hyper-intensive production systems elsewhere.

Currently, shrimp production faces several problems that influence its development and consolidation worldwide. A Global Seafood Alliance 2022 survey to industry stakeholders mentions feed cost, market prices, diseases, and broodstock quality as the most relevant (Nikolik, 2022).

Feed Cost: Ingredients used for shrimp feed formulations have had marked increases in the past decade, with fishmeal and fish oil at average prices of US$1496/ton and US$2348/ton, respectively (BCRPData, 2023a, 2023b). The cancellation of the 2023 Peruvian anchovy fishery, to guarantee the sustainability of the biomass, has further reduced world fishmeal availability by 10% and fish oil by 30%, year-on-year (White, 2023) forcing prices up to $2600/ton for fishmeal in China (LeBlanc, 2023), and $6000/ton for fish oil (Miranda, 2023). Vegetable protein sources, such as soy and wheat meals, have also shown sharp increases in the last couple of years due to the Russia–Ukraine war and the extended droughts worldwide. After the collapse of the Black Sea Grain Deal in July 2023 (Wintour, 2023), wheat prices have risen another 8%. For an expected world shrimp production of 5.5 million ton, nearly 9 million tons of feed are necessary (at an average feed conversion ratio (FCR) of 1.6). Feed represents between 40%–65% of total shrimp production costs and the free on board price has risen 25% from early 2021. This has a significant impact on the economic viability of the industry.

Market Prices: Shrimp prices in Ecuador dropped from US$5.80/kg to $5.00/kg from January 2020 to January 2021, during the COVID-19 pandemic, before increasing to $6.80/kg by November 2021, as the markets reopened post pandemic. Nevertheless, a steep decline to $5/kg by July 2023 (Van der Pijl, 2023) has shown that oversupply and slow market demand have eliminated any expectations of a fast recovery. With the Organization for Economic Cooperation and Development Aquaculture (OECD) predicting a 9% decline in fish and seafood prices over the next decade (OECD/FAO, 2023), the economic outlook is for industry consolidation, needed value chain cost reductions and improved production efficiency.

Disease: While all cultured species have had some impact from diseases, it is safe to say that shrimp has been affected the most. How much of an impact? Flegel et al. (2008) reported losses of around 22%/year, equivalent to US$1 billion. More recently, Shinn et al. (2018) put that figure at US$4 billion/year during 2009–2018, caused mainly by white spot syndrome virus (WSSV) and accute hepatopancreatic necrosis disease. Asche et al. (2021) modeled the impact of disease on shrimp concluding “the presence of disease increases breakeven price significantly and thereby increases the probability of losing money as well as increase the risk.” The lack of a highly developed immune system in shrimp prevented development of the industry in Asia for a long time, as the reliance on wild P. monodon stocks created a vicious cycle of infection-antibiotic treatment-reinfection. The introduction of Specific Pathogen Free (SPF) white shrimp, L. vannamei (Alday-Sanz et al., 2018), and improved management, resulted in a dramatic increase in production from 2000.

Broodstock Quality: MacIntosh (2010) indicated that selective breeding for rapid growth based on SPF lines for white shrimp has been successful at improving survival, reducing FCRs and the fish in: fish out ratio, and shortening the grow out cycle, thus reducing energy demands and overall production costs. With this, a 44% reduction in culture time to 25 g (128–74 days), over 85% survival, 20% reduction in FCR (1.6–1.3), and 44 ton/ha/year over six generations were possible for white shrimp in Thailand. However, with the onset of diseases, selection strategies have changed. Farmers in Ecuador decided to use surviving individuals from WSSV-infected production ponds as breeders. Survival was their primary goal, with expectations of developing Specific Pathogen Tolerant (SPT) strains, which limit the effect of disease if it occurs (Alday-Sanz et al., 2018). Expected challenges were that hatcheries could become a source of disease, and that tolerance would not transfer from generation to generation due to poor heritability. Nevertheless, the gamble paid off. With the incorporation of better management strategies, including automatic feeding and aeration, Ecuador is now the leading exporter of shrimp in the world. On the other hand, India which also expanded production significantly in the past few years is now dealing with an increase in crop failure rates which some attribute to a lack of robustness to changing environmental conditions of the new genetic strains in the pond (Kumar, 2022).

What are the opportunities to reduce production costs and improve production efficiency?

If we look at the feed costs, new manufacturing processes, like extrusion (Miranda, 2023), have shown clear benefits in FCR improvement and a reduction of residual organic matter in the ponds. This has taken hold in Ecuador, but not India, due to resistance by farmers to pay even more for the most expensive item in their production cost structure. Similarly, automatic feeding and aeration have shown its benefits for better-feed usage, but equipment and installation costs deter some producers from incorporating them. At present, around 17% of farm area in Ecuador uses automatic feeders and aeration, with expectations for the country to increase exports significantly in the coming years, as more farming sectors incorporate better technologies (Yahira Piedrahita, “Will Ecuador continue to grow its shrimp production?” at the Global Shrimp Forum, 2023). Understanding carrying capacity in changing culture conditions (i.e., dry or wet seasons, El Nino Southern Oscillation (ENSO) events, or increased temperatures due to climate change) is essential to avoid past mistakes when deciding to increase stocking densities to improve yields. On the other hand, fishmeal and fish oil limitations present a major challenge for industry growth, as farmed crustaceans (shrimp, prawn, crayfish, and crab) are the top consumers of available fishmeal, with 30% (Johannessen, 2023). This means that new protein sources like insect meal (black solder fly larvae), unicellular proteins (yeast, bacteria, fungi, and algae) and vegetables (Pea, Faba) (Geerts, 2023) will play a relevant role. However, volume and cost are still very much a limitation for these supplies. Similarly, as we consider the evolution of the industry form semi-intensive to more intensive systems in some regions (see Horton, 2022), and the incorporation of economically viable recirculatory aquaculture system (RAS) systems, molecular-assisted genetic selection for high growth strains, more adaptable to new protein use, will be needed.

The current geopolitical situation is also affecting the market. This will lead to consolidation and better vertical integration to reduce production costs, better managing the price downturn. Streamlined and continuous offer of high quality, traceable, shrimp from certified farms would reduce seasonal price variations and eventually lead to production contracts of insured crops. This will improve financial certainty for farmers. Certifiable, more controlled (intensive) production will also improve the narrative of the industry in terms of sustainability. This and the consumer shift to more nutritious and healthy products will encourage consumption (Bianchi et al., 2022; Gulmans, 2023), thus opening the door for an expected increase in production volume (i.e., from Ecuador or other areas). Hyper-intensive RAS production needs to complete its validation process, but when it does, will eventually contribute to a reduced carbon-footprint by establishing production areas near niche markets (live shrimp, head-on, never frozen shrimp, etc.)

As we intensify shrimp culture, continuous production becomes feasible in more regions. Better disease prevention and diagnostics are essential. The advent of genomics has made it possible to identify family traits and select for disease tolerance or resistance to specific pathogens (Kumar, 2022). At present, evidence of selection for WSSV tolerance shows promise, with some commercial genetic lines offering organisms selected for both growth and disease tolerance. This was considered impossible by the industry 10 years ago. Quick-detection CRISPR-Cas 9 kits for multiple diseases will be essential on-site, to manage pathogens better (see Sullivan et al., 2019).

Improvements in breeding where selected lines are the result of natural mating and non-ablation of spawners, certified with improved disease challenges for early mortality syndrome climate and appropriate disease challenges for enterocytozoon hepatopenaei and WFD will contribute to improving genetic programs. These will continue to be based in SPF broodstock from a wide genetic pool nucleus, using molecular assisted selection for specific traits, like growth (MacIntosh, 2010), disease tolerance (Kumar, 2022), feed use efficiency (Dai et al., 2019) and physiological robustness (Villarreal-García, 2022). On the other hand, the development of new genetic lines for P. mondon will lead to the incorporation of a more consistent supply of larger sizes to the market (Van der Pijl, 2023).

Juarez et al. (2022) identify differences among production systems in terms of biosecurity, use of water, aeration and energy efficiency per ton of product. These differences are relevant for the way we deal with industry problems. Some hatcheries offer specific genetic lines for these production systems. In general, fast growing shrimp lines are the best option in well-managed systems. For example, Fletcher (2023) quoted Robins MacIntosh (CEO Homegrown Shrimp) indicating that it is possible to produce 34-g white shrimp in 82 days, without a reduction in survival, using a RAS system. However, pond performance is an interaction between genetics, available feed quality and environment. When any of these three factors change, management has to adapt. Using a fast growth line means the expected weekly growth rate is higher requiring more feed. Boyd and Hanson (2010) indicated that only 10% of total oxygen is available for shrimp in biofloc systems. Faster shrimp growth results in a larger biomass that requires an increase in available oxygen levels in the pond to adjust the carrying capacity as the metabolic demands of shrimp increase (Villarreal et al., 2022; Villarreal-García, 2022). MacIntosh (2010) suggested that around 5.8 mg/L available oxygen in the pond contributes to keep shrimp healthy when they are metabolizing and growing at a faster rate (Fletcher, 2023).

As we move toward production systems that are more sustainable and efficient, a better understanding of shrimp biology and the dynamics of the interactions with the environment is needed. The shrimp industry is positioned to advance significantly in the coming years if it can integrate available knowledge to the industrial innovation process.