The Nonlinear Library EA - Quantifying and prioritizing shrimp welfare threats by Hannah McKay
Jun 13, 2024
27:51
Welcome to The Nonlinear Library, where we use Text-to-Speech software to convert the best writing from the Rationalist and EA communities into audio. This is: Quantifying and prioritizing shrimp welfare threats, published by Hannah McKay on June 13, 2024 on The Effective Altruism Forum.
Citation: McKay, H. and McAuliffe, W. (2024). Quantifying and prioritizing shrimp welfare threats. Rethink Priorities.
https://doi.org/10.17605/OSF.IO/4QR8K
The report is also available on the Rethink Priorities
website
and as a pdf
here
.
Executive summary
This is the fourth report in the Rethink Priorities Shrimp Welfare Sequence. In this report, we quantify the suffering caused to shrimp by 18 welfare threats to assess which welfare issues cause the most harm.
See a
complete description of the methodology here. We focused on penaeid shrimp in ongrowing farms and broodstock facilities. Incorporating uncertainty at each step of the model, we estimated the prevalence, intensity, and duration of pain caused by each welfare issue. The intensity was based on the Welfare Footprint Project's
Pain-Track categories, and 'pain' refers to their definition of pain, encapsulating both physical and mental negative experiences (
Alonso & Schuck-Paim, 2024a). We collapse different pain type estimates into a single metric: 'Disabling-equivalent pain'. See the results in Figure 1.
The average farmed shrimp spends 154 hours in disabling-equivalent pain (95% Subjective Credible Interval (SCI): [13, 378]). If we assume that 608 billion penaeid shrimp die on ongrowing farms annually (i.e., including those that die pre-slaughter;
Waldhorn & Autric, 2023) then mean values imply that they experience 94 trillion hours of disabling-equivalent pain a year (95% SCI: [8 trillion, 230 trillion]).
The highest-ranking threats are chronic issues that affect most farmed shrimp. The top three are high stocking density, high un-ionized ammonia, and low dissolved oxygen. Threats ranked lower are broadly acute, one-off events affecting only a subpopulation (e.g., eyestalk ablation, which affects only broodstock). However, the credible intervals are too wide to determine the rank order of most welfare issues confidently.
Box 1: Shrimp aquaculture terminology
The terms 'shrimp' and 'prawn' are often used interchangeably. The two terms do not reliably track any phylogenetic differences between species. Here, we use only the term "shrimp", covering both shrimp and prawns. Note that members of the family Artemiidae are commonly referred to as "brine shrimp" but are not decapods and so are beyond the present scope.
We opt for the use of Penaues vannamei over Litopenaeus vannamei (to which this species is often referred), due to recognition of the former but not the latter nomenclature by ITIS, WorMS, and the Food and Agriculture Organization of the United Nations (FAO) ASFIS List of Species for Fishery Statistics Purposes.
The shrimp farming industry uses many terms usually associated with agriculture - for example, 'crops' for a group of shrimp reared together, 'seed' for the first shrimp stocked into a pond, and 'harvest' for collecting and slaughtering shrimp. For clarity, we broadly conform to this terminology. Although we acknowledge animal welfare advocates may prefer terminology that does not euphemize or sanitize the experience of farmed shrimp, here we favor ensuring readability for a wide audience.
Introduction
We began the Shrimp Welfare Sequence by asking whether the Animal Sentience Precautionary Principle (
Birch, 2017, p. 3) justifies implementing reforms in shrimp aquaculture. The first three posts collectively provide an affirmative answer:
More shrimp are alive on farms than any other farmed taxa
Half of them die before slaughter, suggesting that some of the welfare threats they endure must be serious.
The welfare threats shrimp experience are varied, ranging from poor water quality to environmental deprivation to inhumane slaughter.
Unfortunately, it is probably n...
Citation: McKay, H. and McAuliffe, W. (2024). Quantifying and prioritizing shrimp welfare threats. Rethink Priorities.
https://doi.org/10.17605/OSF.IO/4QR8K
The report is also available on the Rethink Priorities
website
and as a pdf
here
.
Executive summary
This is the fourth report in the Rethink Priorities Shrimp Welfare Sequence. In this report, we quantify the suffering caused to shrimp by 18 welfare threats to assess which welfare issues cause the most harm.
See a
complete description of the methodology here. We focused on penaeid shrimp in ongrowing farms and broodstock facilities. Incorporating uncertainty at each step of the model, we estimated the prevalence, intensity, and duration of pain caused by each welfare issue. The intensity was based on the Welfare Footprint Project's
Pain-Track categories, and 'pain' refers to their definition of pain, encapsulating both physical and mental negative experiences (
Alonso & Schuck-Paim, 2024a). We collapse different pain type estimates into a single metric: 'Disabling-equivalent pain'. See the results in Figure 1.
The average farmed shrimp spends 154 hours in disabling-equivalent pain (95% Subjective Credible Interval (SCI): [13, 378]). If we assume that 608 billion penaeid shrimp die on ongrowing farms annually (i.e., including those that die pre-slaughter;
Waldhorn & Autric, 2023) then mean values imply that they experience 94 trillion hours of disabling-equivalent pain a year (95% SCI: [8 trillion, 230 trillion]).
The highest-ranking threats are chronic issues that affect most farmed shrimp. The top three are high stocking density, high un-ionized ammonia, and low dissolved oxygen. Threats ranked lower are broadly acute, one-off events affecting only a subpopulation (e.g., eyestalk ablation, which affects only broodstock). However, the credible intervals are too wide to determine the rank order of most welfare issues confidently.
Box 1: Shrimp aquaculture terminology
The terms 'shrimp' and 'prawn' are often used interchangeably. The two terms do not reliably track any phylogenetic differences between species. Here, we use only the term "shrimp", covering both shrimp and prawns. Note that members of the family Artemiidae are commonly referred to as "brine shrimp" but are not decapods and so are beyond the present scope.
We opt for the use of Penaues vannamei over Litopenaeus vannamei (to which this species is often referred), due to recognition of the former but not the latter nomenclature by ITIS, WorMS, and the Food and Agriculture Organization of the United Nations (FAO) ASFIS List of Species for Fishery Statistics Purposes.
The shrimp farming industry uses many terms usually associated with agriculture - for example, 'crops' for a group of shrimp reared together, 'seed' for the first shrimp stocked into a pond, and 'harvest' for collecting and slaughtering shrimp. For clarity, we broadly conform to this terminology. Although we acknowledge animal welfare advocates may prefer terminology that does not euphemize or sanitize the experience of farmed shrimp, here we favor ensuring readability for a wide audience.
Introduction
We began the Shrimp Welfare Sequence by asking whether the Animal Sentience Precautionary Principle (
Birch, 2017, p. 3) justifies implementing reforms in shrimp aquaculture. The first three posts collectively provide an affirmative answer:
More shrimp are alive on farms than any other farmed taxa
Half of them die before slaughter, suggesting that some of the welfare threats they endure must be serious.
The welfare threats shrimp experience are varied, ranging from poor water quality to environmental deprivation to inhumane slaughter.
Unfortunately, it is probably n...