LATEST UPDATE: September 2025
Billions, and perhaps even trillions, of aquatic animals are killed every year for human use — a number that is projected to continue increasing in the coming years. A larger and larger portion — now greater than 50% — of these individuals are being supplied by aquaculture, an intensive form of animal farming analogous to practices which have become commonplace for the production of chickens, pigs, cows, and other land animals. And just like with factory farming land animals, comprehensive details on the inner workings of aquaculture can be difficult to obtain for a variety of reasons.
This exclusive Faunalytics Fundamental illustrates the current understanding of aquaculture using the best available data to inform advocates and people working towards solutions to the problems aquaculture creates. For further consideration, please check out our blog about what we included and what we left out.
Meet The Animals
Aquaculture is a broad and multi-faceted industry, comprising the production and slaughter of hundreds of species of aquatic wildlife. As such, it would be impossible to give a comprehensive look at all of the animals used within the system. Below, we take a look at four of the most common categories of animals — however, it’s important to note that, even within these categories, there may be dozens of species, each with their own special characteristics, quirks, and welfare needs.
Carp
are curious and careful individuals with a strong tendency to work in groups.
- A Variety Of Social Bonds – They can be solitary or crave companionship, depending on the individual
- A Memory For Trauma – They remember where they’ve been caught before and will avoid those places
- Group Dynamics – They will work together, foraging in groups — though some may be more forceful than others
Tilapia
are socially complex species with a tendency towards rigid hierarchies.
- Rooted In Resilience – They are hardy species that can thrive in relatively harsh conditions
- Warm & Outgoing? – Some may prefer warmer water temperatures — and those who do are more proactive
- Top Of The Pyramid – The males of the species fight and struggle to establish a social hierarchy
Shrimp
have behaviors as intricate and varied as their species are numerous.
- Complexity & Caution – They have distinct and variable personalities that go beyond a simple shy/bold dichotomy
- By The Numbers – There are more shrimp alive at any one time on aquaculture farms than any other farmed taxa
- Strong Support For Sentience – Though understudied, there is strong support for recognizing shrimp sentience
Oysters
are intriguing, with much to teach us about non-human life and behavior.
- Hearing & Listening – They ‘hear’ waves to regulate their wake and rest, and are affected by underwater noise
- Key To Their Environments – They can be keystone species, helping to shape their habitat and supporting other species
- Edge Cases – Their unique nature has inspired much debate, but vegans still don’t consume them
Attitudes
A general optimism surrounds the aquaculture industry: according to its proponents, fish can provide healthy, protein-rich food, and aquaculture has been seen as a way to move away from wild capture fishing and towards a more secure and sustainable food system. This is evidenced by a tripling in aquaculture production from 1997 to 2017, which was preceded by a tripling in production from 1987 to 1997. While there is common sense behind the the idea that moving away from wild capture fisheries could be more sustainable, the dividends are not as high as the general public might be led to believe.
Despite a boom in aquatic protein produced through aquaculture, there has not been a substantial reduction in the quantity of fishes taken from our oceans, largely due to a reliance on fishmeal and fish oil from wild caught fishes in farmed fish feed. What’s more, the intensive single-species production style adopted by many aquaculture operations also leaves populations vulnerable to infectious diseases and pests, threatening the welfare of millions of fishes and the security of production.
As aquaculture continues its rapid expansion, it’s increasingly important to understand how the general public perceives the industry, how that perception is influenced by the industry itself, and how to counter false perceptions with the reality of the situation.
Aquaculture & Antibiotics
Infectious diseases are one of the main threats to the health of fishes farmed through aquaculture. Stocking high densities of a singular species in unsanitary water creates ideal conditions for the spread of pathogens. To prevent the death of fishes, and sometimes to promote faster growth, farmers commonly introduce antibiotics into their feed. The high usage of antibiotics increases the chances of bacteria developing genetic resistance that protects them from antimicrobial agents, creating downstream problems for humans, animals, and the environment.
Since a significant proportion of aquaculture — an estimated 37% of production — occurs in open water or along coast lines, and since farmed fish escapes are quite common, it’s easy to understand why antibiotic resistance poses a particular threat to the surrounding environment. Unfortunately, aquaculture’s environmental impact doesn’t end there.
The Environmental Impact Of Aquaculture
Despite aquaculture’s reputation of being a more “sustainable” alternative to the farming of terrestrial animals, the industry still has profound effects on our environment. The emission intensity (greenhouse gas emissions per kilogram of bodyweight) of fishes can vary widely — in some cases, they are more intensive than even pigs and chickens. In the case of certain species like shrimp, the emissions intensity can be significantly higher. Production, processing, and transport of feed, added to all of the activities associated with the rearing of fishes, release millions of tons of greenhouse gasses into the atmosphere each year.
In the graphics below, we explore just how much aquaculture impacts the environment, and how it compares to other industries.
The Big Problem With The Small Body Problem
So far, we’ve concentrated on the impacts of the aquaculture industry as a whole, looking at aggregate numbers and issues of scale. However, there is another problem lurking within aquaculture when we look at the issue on a zoomed-in level.
It is no secret that commonly farmed fish species — salmon, shrimp, trout, etc. — tend to be smaller in terms of their mass than commonly farmed land animals. This is referred to as the Small Body Problem, and from the perspective of animal welfare, this has enormous implications.
As the old adage goes, both a ton of feathers and a ton bricks weigh the same amount — but you need much more of one than the other to reach the same weight. In order to produce the same amount of meat, one must slaughter an exceptionally higher number of small animals compared to large animals. If individuals from different species experience similar or comparable levels of suffering, switching to consuming the smaller species will result in more total suffering due to the greater number of individuals slaughtered.
This Small Body Problem is exacerbated by the conditions in which large and small animals are often farmed. For example, cows are most likely to be given access to pasture and, in intensive systems, are allotted more space than their smaller counterparts. Chickens, on the other hand, rarely if ever have an opportunity to experience the outdoors, and more often than not experience terribly uncomfortable lives in cramped, ammonia-filled warehouses being crushed by the weight of their own bodies. In aquaculture, stocking densities are some of the highest of any other type of animal agriculture.
The Small Body Problem highlights just how much we need to take aquatic animal welfare more seriously. Until very recent history, the vast majority of people have seen fishes as unfeeling and non-sentient, with a consciousness far too different from ours to take into account. Fortunately, that tide is turning.
The Painful Truth About Fish Sentience
People’s perceptions of the lived experience of fishes tend to differ from that of land animals. There seems to be a consensus among the general public that fish do not share the same level of consciousness that other land animals possess, a sentiment that is very much incorrect. Despite a relatively lower amount of research in the area, there have been swaths of evidence that show fishes have the capacity to solve puzzles, use tools, have a personality, and perhaps most importantly: experience pain and suffering.
Establishing markers of sentience can be very challenging and may not always be definitive. However, based on the behaviors, evolution, and physiology of fishes, it would be naive to suggest they do not possess levels of sentience similar to land animals. This emphasizes a need for continued research on the welfare needs of fishes to support policies that will protect the billions of aquatic individuals farmed through aquaculture every year.
Industry Opposition
As the aquaculture industry continues to grow globally, it hasn’t been an entirely smooth upward trajectory. The industry has received pushback on a number of proposed endeavors, most notably octopus farming. Demand for consuming cephalopods exists and a number of companies are trying to capitalize on the market, most notably Nueva Pescanova, who are planning on building a roughly 567,000 square foot octopus farm. This endeavor has been met with intense backlash, primarily founded on previous failures to farm octopods, as well as their immensely complex behaviors. This points towards a correlation between the perceived sentience of an animal and people’s lack of willingness to eat them. This further highlights a need for research into the behaviors and sentience of aquatic animals, a relatively less understood subject of study, in an effort to place more importance on their lives and experiences.
This Faunalytics Fundamental has provided a visual overview of just some aspects of the complex and multi-faceted aquaculture industry. Though we’ve tried to give you the deep overview of the most important topics, there is much more than could be covered. Whether you’re new to the issue of aquaculture and advocacy, or have been in the space for a long time, we think you’ll find the data above to be useful in a variety of ways, and we’d love to hear how you use it in your work.
We hope the data presented here also encourages advocates to ask questions about how to be more effective and how best to invest our limited advocacy resources:
- Considering the degree to which shrimp farming is projected to rise in the coming 5-10 years, how much should advocates be shifting our focus to shrimp consumption and welfare?
- From an environmental perspective, fish farming can be seen as roughly similar to pig or chicken farming, but it is still significantly less impactful that farming cows. How can advocates make sure that a transition from cow consumption doesn’t place further pressure on aquatic animal populations, both farmed and wild?
- Are there ways that advocates can push aquatic species sentience research forward, so the lingering “questions” around the topic become settled?
- Is there a way that advocates can leverage “charismatic species” such as octopi in their work to promote concern for other species used in aquaculture?
These are questions advocates should think about and potentially research further.
There is so much more work to be done to give advocates the insight they need to choose the most effective ways to help animals. Please donate generously now to help us bring you and other advocates this crucial information.
This project was supported by Coefficient Giving.
This resource was produced by Faunalytics in collaboration with Ian Hammond,
as part of the Reducetarian Fellowship.
