Back in 2014, Dr Manoj M Sharma, Director at Mayank Aquaculture Pte Ltd (MAPL) came to the TARS conference to explain his way to farm Penaeus vannamei, the monodon way, producing large size shrimp (40-50g) at low stocking density of 15-20 PL/m2 in Gujarat, India. In 2021, Manoj has reverted to farming black tiger shrimp (Penaeus monodon) which became possible with the recent availability of post larvae from specific pathogen free (SPF) broodstock in India.
As a longtime advocate of farming the monodon shrimp, given the right conditions, Manoj decided to test whether “bringing back the black tiger shrimp is better or a blunder” for him. During TARS 2021, he discussed his reasons for bringing back monodon shrimp production although there is concern on its export potential.
SPF and domesticated monodon broodstock are now available in the region, which Robins McIntosh, CPF, Thailand referred to as the push for the successful expansion of monodon farming in China, Malaysia and Vietnam. Dr Tung Hoang, CSIRO, Australia said that Vietnam produces 250,000 tonnes of monodon shrimp annually using extensive culture models where stocking at 0.5 PL/m2 produces 100g in 90 days and stocking at 1 PL/ m2 produces >100g shrimp in >120 days.
For Manoj, farming monodon in bio-secured farms using the present vannamei model should not be a problem. However, there is a need to keep a close watch on monodon growth and survival, as the carrying capacity of farms has been severely reduced due to repeated vannamei shrimp farming. When vannamei shrimp farming began in Asia, it was supposed to occupy the smaller size (100/kg to 50/kg) shrimp market but gradually, with partial harvesting, it can now occupy all size segments. Therefore, it is essential that he and other farmers understand the market for the monodon shrimp.
History of the monodon shrimp in India
In India, shrimp farming started with its endemic monodon shrimp from 1985 to 2009, until the white spot syndrome virus (WSSV) devastated production, from its peak of 120,000 tonnes in 2005 to less than 80,000 tonnes in 2008.
“Back then, our biggest limitation was the quality of both broodstock and post larvae. We had repeated diseases; WSSV, loose shell, hepatopancreatic virus (HPV), poor growth and external fouling with slow growth. To reach 30 count/kg took 150-200 days. We were desperate until farming of the vannamei shrimp was allowed and the biggest highlight of this was the availability of SPF/ SPR (specific pathogen resistant), disease free and high health broodstock.” Manoj added, “Of course the attraction was the size range accepted by markets and that production can extend to 10 tonnes/ha.”
In India, vannamei shrimp farming began in 2010 and since then, production has been phenomenal. In 2020, 95% of production was vannamei shrimp from 75 billion post larvae. Today, there is hardly any supply of monodon post larvae. “We reached 800,000 tonnes in 2019 and the 20% decline in 2020 was definitely due to production issues as much as the Covid-19 pandemic.”
Increasing costs of production
The problems with vannamei shrimp farming range from lower survival rate to slower growth, higher feed conversion ratio (FCR) and rampant disease outbreaks from Enterocytozoon hepatopenaei (EHP), Vibrio, atrophy of hepatopancreas, running mortality syndrome (RMS) in 5-10g shrimp, white faeces disease (WFD) and more recently, infectious myonecrosis virus (IMNV). WSSV remains the biggest threat with 50-60% of farmers reporting the disease, especially during the post- monsoon season. With the pandemic, disruptions led to drastic increases in costs. In the last three months (since May 2021), shrimp feed prices have increased 8-12%.
Manoj listed issues such as high stocking density and high salinity compounded with high organic load as the recipe for disaster in shrimp farming. It was not only production versus pond carrying capacity but also production area versus water source carrying capacity (Sharma, 2019). “I call this whitewashing in shrimp farming – in summer, it is WFD and in winter and monsoon season, WSSV!”
Disparity in COP
In India, there are clear disparities in the cost of production (COP) between farms in Andhra Pradesh, the leading producing state with 70% of the annual production and the rest of India, in particular Gujarat (Table 1). “Post larvae cost in Andhra Pradesh is almost half that for the rest of India and feed cost is lower. COP in Andhra Pradesh is USD1 less than the rest of India. But international buyers see India as one country,” said Manoj.
Based on costs to produce 70 to 20 count/kg shrimp, Manoj said that achieving a return on investment (ROI) of at least 40% is difficult with small size shrimp. In Andhra Pradesh, farmers have been able to sustain because of better prices for small size shrimp. In August 2021, the ex-farm price for 100 count/kg was INR 180/kg (USD 2.43/kg). However, he added, “To stay in the competition, here in Gujarat, we need to produce large size shrimp,be it vannamei or monodon shrimp.
More on Gujarat
Until recently, Gujarat was the second largest shrimp producing state in India. It won accolades as the most productive with 95% success rates. West Bengal and Odisha have overtaken Gujarat because of hot temperatures during the latter’s summer crop. “Gujarat is famous for the production of size 30-45g shrimp, which I have been promoting aggressively – farming vannamei shrimp the tiger way,” said Manoj.
“Farms in Gujarat used to produce 85% of 20-30 count/kg shrimp until 2017. The downtrend came with slow growth of shrimp. In 2020, production declined to only 20,000 tonnes, versus 50,000 tonnes in 2016 with average 40- 50 count/kg (15-20g). Outbreaks of WFD, EHP and RMS affected farms. “With production and profitability issues, the farming fraternity in Gujarat and Maharashtra are thinking of going back to farming the monodon shrimp.”
Fast growing and SPF monodon shrimp
“We now have this option of fast-growing SPF monodon shrimp such as those from Moana and domesticated broodstock from Madagascar. While wild monodon shrimp has an average daily growth (ADG) of 0.27g, SPF monodon grows 50% faster at 0.47g. I can get 50g shrimp in 120 days as compared with 200 days with post larvae from wild broodstock,” said Manoj.
However, reverting to monodon shrimp farming also comes with uncertainties, from success rate, negative carrying capacity, markets and prices. Of course, there is always the issue of diseases. In his checklist are issues such as broodstock and post larvae quality but most important is the export potential as the vannamei shrimp has already occupied the 5-50g shrimp market. Currently, Vietnam and Bangladesh dominate the monodon shrimp markets in Japan and Europe.
“We then need to reinvent the monodon market and ensure supply, volume and consistency. We need to tie up with the right partners, the right certification program and traceability of antibiotic free monodon shrimp.”
Monodon shrimp at MAPL
In 2021, MAPL ran a monodon shrimp crop using four groups of ponds, each with 10 ponds and modifying stocking density from 10 PL/m2 to 20 PL/m2 (Table 3).
In September 2021, the harvesting of four ponds revealed the following: at stocking density of 15 PL/m2, shrimp grew to 13-19 count/kg (52-77g) in 135 days with an average production of 5.8 tonnes/ha. Survival was 65-70% and feed conversion ratio was 1.4. “We also managed to have 10 count/kg (100g) in 160 days,” said Manoj.
“For us farmers, the key is our business survival. This move is to produce larger shrimp with good margins; we have seen the rise and fall of monodon shrimp farming and the rising cost of producing 50-60 count/kg vannamei shrimp in Gujarat. To stay in the game, I would prefer to produce two tonnes of monodon shrimp with high margins.
“Now we can go back to P. monodon. Infrastructure-wise, we are ready to revert to this shrimp, but can we produce it smartly and sustainably? This is the key factor to bring back the beauty of the black tiger shrimp.”
Manoj M Sharma, 2019. The good, the bad and the ugly of shrimp farming. Aqua Culture Asia Pacific, March/April, p8-13.
This article was first published in the print copy of Aqua Culture Asia Pacific November/December 2021