There have been many arguments, both academically and among laypersons, about the impacts of crop agriculture versus animal agriculture. One popular argument against veganism is that more animals have to be harmed to produce fruits and vegetables than there would be if we farmed animals.
The first counterpoint that vegans tend to make in response to this claim is that most of the crops that we grow are used for animal feed. Some will counter that the grass-fed cattle-farming method would be a solution to this imbalance, as it’s generally believed this will cause less harm to animals. Other considerations are made for the quality of life that farm animals face as opposed to wild animals which have added more complexity to the debate.
The exploitation and killing of arthropods are often completely neglected in this conversation for both people who self-identify as vegan and the general public alike, which is another considerable factor in our efforts to end animal exploitation. Alternative farming strategies such as greenhouse and screenhouse farming have been proposed as a means to cause less harm to field animals and the environment in general. The challenge for people who self-identify as vegan will be to analyze the available literature on these topics in order to one day achieve our vision.
The Least Harm Principle (LHP) has been discussed among academics since the turn of the millennium, with some making the controversial argument that plant agriculture and forage ruminant-based agriculture may be less harmful to animals than plant agriculture. The basis for this assertion, as exemplified in Stephen L. Davis's paper, commonly referred to as the “burger veganism” argument, is that many animals are harmed and killed during the plant farming process such as rodents, raccoons, birds, and rabbits. Several examples were given, including how the mowing of alfalfa caused a 50% decline in the gray-tailed vole population, or how harvesting grain crops caused the mouse population density to drop from 25/ha preharvest to less than 5/ha postharvest. Although migration was considered to be a factor, it was estimated that the mortality rate was 52%.
Overall, it was calculated that 1.8 billion animals would be killed annually to produce plants for food in the United States alone. In comparison, pasture-forage production, with herbivores harvesting the forage, would be the ultimate in “no-till” agriculture because of the low number of times that equipment would be needed to grow and harvest pasture forages. In addition, larger herbivores such as cattle would result in fewer farm animals facing slaughter. Under this model, it was calculated that only 1.35 billion animals would be killed annually to produce a diet containing both plants and animal products.
Another benefit to this model is that ruminants are capable of surviving and producing on diets containing only forages, which humans cannot digest. This means that crops such as soybeans and corn could be fed to humans instead of animals and that lands that may otherwise be too rough to produce crops for human consumption can be utilized for pasture forage. Of course, in all of these calculations, the killing and exploitation of certain animals like arthropods are once again completely ignored.
Other models have been suggested that follow the LHP, the first being presented would be to eliminate commercial agriculture and have each household grow their own plant foods on small plots of land, which is not considered a viable option due to large populations, disproportionate land ownership and the need for society to completely restructure itself. Horsemeat is another alternative, as horses typically grow to be larger than cows. However, this option would already be utilized if consumers were open to eating horses. A final alternative that was presented was that people should hunt for their meat locally, however, this approach would result in far too many hunters hunting a comparatively smaller number of animals. With any LHP approach, there is a consideration of “intentional” harm (farm animals) versus “unintentional” harm (field animals), however, it is noted that a utilitarian approach will not differentiate, as consequences matter more than intentions.
In addition, various schools of thought under the umbrella of consequentialism at some point further refine what is considered “unintentional” versus “intentional” into intended, foreseen, foreseeable, likely and unforeseen consequences. It’s easy to see that in the case of pesticides, the death of animals is intended and is no different than the intended death of animals killed at the slaughterhouse, while the animals killed during tilling are foreseen but not intended. Add to this complexity that as human animals we are selfish and tend to see actions we want to do as causing only unforeseen or likely harm while the actions we oppose as causing intended or foreseen harm and the ethics of any action can quickly become complex.
A complete discussion of this is outside the scope of this article and we will explore it in the future. Suffice it to say that for too long people who self-identify as vegan have brushed off the deaths caused by average plant agriculture since it is generally thought more ethical than animal agriculture, but investigations under various ethical frameworks are not as clear as one would have initially thought. The day we turn veganism into a static list of actions we should and should not do for no other purpose than to have a word grouping those actions to self-identifying as such is the day veganism falls apart.
There were various issues with Davis’s position; even though it does not change the high-level concern, we will quickly review them here. The first group of issues centred around some discrepancies in the original calculation where some research had shown the numbers may not be as high as he indicated.
For example, some argued that it was incorrect to use per capita instead of the total number of animals killed. Davis assumes that crops only and crops with ruminant pasture take the same total amount of land and would feed identical numbers of people. To get a more accurate estimate, the number of animals that are killed per consumer should be calculated. According to Davis, the number of wild animals killed per hectare in crops-only production is twice that of ruminant pasture. If this is true, as long as crop production uses less than half as many hectares as ruminant pasture to produce the same amount of food (which it does), a diet consisting of only plants will still kill fewer mammals than an omnivore diet.
Another issue with Davis’s calculations based on the two aforementioned studies is that neither of those studies was conducted in the continental United States and the science of estimating the mortality rates in field animals is still a relatively new branch of discovery, with even Davis himself acknowledging that more research is needed.
The second group of issues relates to Davis’s focus only being on the number of animals killed, as both utilitarians and deontologists are also concerned about non-lethal mistreatments like confinement or physical mutilation. Some point out that, although grass-fed cattle would have some space to roam, they are still subject to painful practices like castration, branding, tagging, dehorning and unnatural breeding. These cattle are transported over long distances in extreme temperatures without food, water or protection to be painfully slaughtered, in contrast to the wild mice that can live freely and practice natural habits until their death in a harvester.
The last group of issues is that not all life needs to be brought into existence if their lives are deemed to be painful and unpleasant. In the case of farm animals, it is arguable that their life is worth living. Some also argue that a diet consisting only of plants is better for human health and cheaper, allowing more funds to go to charity and other projects.
Two positive attributes of Davis’s publications should be noted concerning our vision. The first is that considering how ridiculed some have been for their positions on animal exploitation, such positions show how far this topic of conversation has progressed. Even if we may not necessarily be happy with the direction the conversation is headed, it is positive that exploitation theory is not being ignored but rather pushed in new directions. Secondly, not only has this compelled us to pay more attention to farming methods, but it has also brought more attention to the sheer size of animal carcasses as they pertain to achieving our vision. For example, roughly 200 chickens would have to be slaughtered to produce the same amount of meat as one cow, which represents intermediate questions and concerns that show the potential contributions of Davis’s “burger veganism.”
As we mentioned, none of these studies consider the death and exploitation of all animals, including but not limited to arthropods and human animals like slaughterhouse workers, nor do they consider the impact of animal agriculture on other factors like climate change, zoonotic disease, or the antibiotic crisis. The externalities of animal agriculture would likely be significantly reduced if all animal agriculture would be limited to foraged-based ruminants only, but it would also not be zero.
In a previous article, we briefly looked at the exploitation of arthropods in a broader context but not specifically to estimate this in the context of plant agriculture. We will leave this mainly unexplored for now, but it’s almost certain that the impact would be significant. Others have tried to partially address these issues. It is estimated that between 200 to 900 million insects are present per hectare of farmland and it is clear that this issue must be addressed to get a complete picture of the exploitation caused by plant agriculture.
It has been theorized that arthropods are facing a three-fold attack as a result of agriculture. The first is pesticides and the second is herbicides, with both the treated land area and potency continually increasing. This is disastrous to various insect species which rely heavily on plants for survival. Intensification of cattle grazing is the third way that the insect population is decimated, with just under half of developed nations’ land dedicated to pasture and supporting nothing but grass and the cattle that feed upon it.
Without a doubt, accounting for all animal deaths would drastically change the picture presented above; it is likely that for the standard method of plant agriculture with mechanical harvesting and pesticides, some form of animal agriculture such as cows entirely ruminant-pasture fed, hunting or fishing, could lead to fewer animal deaths overall. We have not discussed or presented research specifically addressing hunting or fishing, but it’s easy to see that while the numbers might not be the same as those presented for pasture-foraged cows it is in the same range and does not materially change any of the arguments presented.
While it is likely true that for one person in a vacuum we can come up with a scenario that eating some animals by intentionally killing them for food causes less death and exploitation than eating some vegetables, it does not scale to the entire population of our planet. There are various important implications to this lack of scalability, the least of which is to make the achievement of our vision impossible. Additionally, it is, at least in theory, possible to grow vegetables without exploiting any animals while it will never be possible to kill animals for food without exploiting them. Supporting methods of agriculture that, at least on paper, can one day bring about our vision enables further research and economies of scale necessary to make these advancements possible.
This leads us to a method of farming that got a large boost during COVID-19, has seen both increased price competitiveness and availability, that not only causes much less killing and exploitation than standard plant or animal agriculture but can in some cases be consistent with our vision of ending animal exploitation. The type of agriculture we are referring to is greenhouse or screenhouse cultivation.
During COVID-19, we all experienced food shortages and the public was starting to ask questions. Greenhouse farmers made public statements to the effect that they could easily supply the market with fruits and vegetables all year long at reasonable prices but our society had not seen fit to give them access to preferential electricity rates that other sectors of the economy have access to, such as mining, extraction and forestry. It became quickly obvious to everyone that food security was at least as important as having any of those products. Therefore, in some provinces greenhouse farmers were also given access to the lowest electricity enjoyed by other sectors of the economy. We have seen not only increased availability of greenhouse-grown produce but also more competitive pricing.
Greenhouse-grown fruits and vegetables often avoid using pesticides, whether organic or inorganic, and they are also generally grown, harvested, watered and fertilized in different ways than conventional methods. In comparison to the standard method used for most produce available on grocery shelves, greenhouse agriculture leads to a significant reduction in the exploitation of animals, and potentially, in some cases, none at all.
Despite the general perception that open-field farming is more eco-friendly with a minor visual impact, a study of Mediterranean tomato farming, measured using life cycle assessment (LCA) methodology, demonstrated that the environmental impact was greater for open-field cultivation; additionally, a higher economic return was reported for greenhouse farming.
An Iranian study of cucumber and tomato farming practices found similar results for cucumbers but reported a higher environmental impact for greenhouse tomato production, mainly due to the use of natural gas in the heating system and more overall diesel fuel required. A Spanish study of green bean farming, using LCA methodology as the measurement, showed that open-field farming has the highest environmental impact compared to screenhouse cultivation, particularly due to lower crop yields. This study also found that misting systems for screenhouse farming are justified due to increased crop yield. The current evidence shows that, under most conditions, greenhouse farming causes less environmental impact and animal exploitation.
Although Davis’s “burger veganism” struggled to stand up to rigorous scrutiny, many of his points are relevant to the ongoing conversation about the achievement of our vision. With a lot of propaganda being aimed at justifying animal agriculture, it’s important for the public to be aware of the specific facts and numbers surrounding both crop and animal agriculture. Additionally, we need to take into account all animals like arthropods in our calculations, which is why greenhouse and screenhouse farming are so beneficial in our quest to end the exploitation of animals.
It’s a great opportunity to support a growing industry that can finally be concordant with the achievement of our vision in a timely manner. We encourage everyone to choose produce grown in a greenhouse or screenhouse over standard crop production methods whenever possible. As veganism continues to grow and evolve, more analysis and discussion are needed to make informed decisions about our consumption choices to bring about our vision.