Shrimp Welfare Project Makes Shrimp Farming More Humane

The Shrimp Welfare Project (SWP) lets shrimp farmers use free electrical stunners, which are believed to reduce suffering during the slaughter process. Each stunner generally costs $55,000, and can stun up to 5 metric tons of shrimp (hundreds of thousands of average sized-shrimp) per hour.

Electrical costs to operate stunners are only around $1 per hour, but the high initial purchase price remains a significant barrier to widespread adoption. SWP is solving this problem.

How It Works

SWP approaches retailers and offers to buy stunners for their supply chain provided that:

  • Farmers in the supply chain agree to stunning a minimum number of shrimp each year.
  • The retailer agrees to prioritize buying shrimp that have been stunned.

Since being founded in 2021, SWP has secured 17 such agreements and distributed 6 stunners.

Note: After an agreement is reached, it typically takes about 6 to 8 months for SWP to distribute the stunner and have it operational. The remaining 11 stunners are still being processed, but should be operational shortly.

Cost-Effectiveness

We estimate that on average, donating one dollar to SWP results in thousands of additional shrimp being stunned.

You can find our cost-effectiveness analysis here. Please note that these numbers should not be taken literally, and are only intended to provide a general sense of how cost-effective we think SWP's work is.

Key Limitation: Monitoring Stunner Usage

A key limitation in our cost-effectiveness analysis is that SWP is currently unable to monitor stunner usage. Thus, our cost-effectiveness analysis relies on the assumption that companies will not stun more (or less) shrimp than they agreed to.

We believe this is a significant limitation. However, SWP has provided two mitigating factors:

  • When a farmer signs an agreement to stun shrimp, there is a retailer who has agreed to buying those stunned shrimp. This creates accountability for both parties—farmers risk damaging relationships if they fail to uphold their agreement, while retailers risk public backlash if they don't follow through on their agreement.
  • SWP is currently working towards being able to monitor stunner usage, so this may cease to be an issue in the near future.

That said, Vetted Causes remains skeptical of unmonitored agreements, and questions how strong the first mitigating factor truly is. We could not find evidence of significant consumer pressure on retailers to stun shrimp, so we wouldn't be surprised if public backlash for noncompliance is limited.

Despite this uncertainty, even if stunners are used at only a fraction (e.g., 1%) of the agreed rate, millions of shrimp would still benefit. Additionally, given the significant logistical burden for farmers to accept stunners, it seems unlikely that the stunners are going completely unused.

Other Work

SWP's other work includes:

  • Helping farmers implement sludge treatment to improve water quality for shrimp.
  • Helping farmers implement chill killing—a method of shrimp slaughter that is not as humane as stunning, but is more economically feasible.
  • Providing training and resources to help farmers improve shrimp welfare.
  • Conducting research to guide SWP's actions.

To learn more about SWP's other work, click here.

What SWP Would Do With Additional Funding

If SWP received additional funding, their top priorities would be distributing more stunners, and implementing a system that allows them to monitor stunner usage.

You can learn more about SWP's plans through their 2025 funding proposal, which can be found here.

Room for Improvement

We believe SWP could improve by providing more information to the public on their website. In particular, we think SWP could:

  • Make the assumptions in their impact estimates clearer.
  • Provide more citations and/or explanations justifying the numbers behind their impact estimates.
  • Provide more information to the public regarding the status of each stunner (i.e. out for delivery, arrived, etc.).

We believe donors would appreciate this information, and providing it could lead to additional donations for SWP.

Conclusion

While SWP's work has its limitations (particularly regarding monitoring stunner usage), we still believe SWP is likely improving the lives of numerous shrimp at a relatively low cost. We also believe that additional funding would allow SWP to help billions of additional shrimp.

Accordingly, we consider SWP a strong option for donors interested in helping shrimp.

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References

References were last checked on April 27, 2025.

    5.
    Global Electrical Prices

    Note: Voltage × Current = 220 V × 25 A = 5,500 W = 5.5 kW. 5.5 kW × $0.11/kWh = $0.61 per hour

    6.
    SWP: Humane Slaughter Initiative

    Note: SWP informed us that as of April 2025, 17 agreements had been made with 6 stunners distributed. SWP also informed us that it typically takes 6 to 8 months for SWP to distribute a stunner and have it operational once an agreement has been signed.