Animal Advocacy Research Fund – Round 3

I (Persis Eskander) was awarded funding in Round Three of the ACE Animal Advocacy Research Fund. Below is a copy of my grant proposal (with some minor redactions of private information).

Examining the harm caused by crop cultivation to vertebrate wild animals in the United States

Abstract

In seeking to minimise the harm caused to livestock on farms, many people have adopted a plant-based diet. However, crop cultivation is not free from suffering. In the United States, animals considered “pests” such as rodents are killed through baiting, fumigation, or traps. Agricultural practices such as tillage (plowing, disking, and harrowing), sowing and harvesting also kill, maim or dislocate (leaving them susceptible to death from exposure) animals living in the fields. Plant-based foods are necessary for human health and development, but our reliance on agriculture does not mean we are incapable of reducing the suffering caused by agricultural practices in crop cultivation. As it is difficult to conclusively determine which crops and agricultural practices cause the most harm, this foundational research project will examine the mortality rates of vertebrate wild animals due to agricultural practices in the United States. We can understand the impact of crop cultivation on vertebrate wild animals by examining the calories per hectare and breaking down plant-based consumption into three macronutrient categories: carbohydrates, protein and fat. Within these categories, examining the cultivation methods of the most nutrient-dense whole foods will allow us to identify a baseline number of vertebrate animals killed per capita on a plant-based diet. This is because the most nutrient-dense whole foods meet daily macronutrient requirements in smaller quantities than less nutrient-dense foods. The agricultural practices analysed fall into the following categories: population control and cultivation. The mortality rates are estimated according to changes in the population densities of vertebrate wild animals as a result of these activities. As a result, this research project will identify which current agricultural practices and tangentially which plant-based whole foods cause the least harm to vertebrate wild animals. This work presents a unique opportunity to unite the agricultural industry, plant-based diet advocates and reducing wild-animal suffering proponents with a common goal: to find cost-effective, humane and sustainable solutions to vertebrate wild animals in crop cultivation.

Problem

There is no doubt that plant-based diets cause some harm to free-living wild animals. That plant-based diets may actually cause more suffering than omnivorous diets containing large herbivores has been popularly advocated (Davis, 2003) and disputed (Matheny, 2003; Middleton, 2009). Discussions on the normative ethics of the unintentional harm in crop cultivation versus the intentional rearing and slaughter of farmed animals for consumption have also been canvassed (Archer, 2011; Lamey, 2007).

For those swayed by the magnitude of the suffering of field animals in crop cultivation, no further examination of methods to reduce their suffering has so far been considered beyond adopting an omnivorous diet containing large herbivores. For those persuaded by estimates that plant-based diets do cause less harm, little further moral consideration has been given to the vertebrate wild animals that continue to suffer due to agricultural practices. It likely that little thought has been given to policies that might reduce the suffering of vertebrate wild animals in agriculture because it occurs on a large and complex scale. However, the factors that make wild-animal suffering advocacy highly intractable in general do not apply here. That is, crop cultivation is not a practice that is far removed from human experiences; there are economic and ethical incentives; and there are viable solutions to minimising, if not eliminating, suffering.

There is a dearth of analysis in a promising field of research through which we have the opportunity to reduce wild-animal suffering. According to data gathered by the World Bank, agricultural land comprises 44.6% of total land area in the United States (“Agricultural land (% of land area) | Data,” n.d.). Within total agricultural land area, arable land constitutes 37.9% (“Arable land (% of land area) | Data,” n.d.). Wild animals are drawn to fields because of the access to water, food and shelter (Witmer, 2010). When they reach high densities, wild animals can cause significant damage to crops (Witmer, 2010). Given that the amount of land we cultivate and the way we choose to cultivate it are factors we have the capacity to change, understanding the impact of agricultural practices on wild animals is an important and significant undertaking.

Research idea

This research project will examine the agricultural practices that harm vertebrate wild animals. These activities are divided into the following categories:

  • Population control: baiting, fumigation and trapping.
  • Cultivation: tillage, sowing, and harvesting.

The crops are selected according to the most nutrient-dense whole foods according to calorie per hectare and within the following three macronutrient categories:

  • Carbohydrates;
  • Protein; and
  • Fat.

The extent of the harm caused depends on the following variables:

  • The methods applied to selected crops;
  • The annual per capita consumption requirement as part of a plant-based diet;
  • The land area required;
  • The frequency of cultivation and population control activities; and
  • The animal populations per hectare on the selected crop fields.

Conditional on the variables above, the most nutrient-dense whole foods will meet daily macronutrient requirements in smaller quantities than less nutrient-dense foods. With this data, it will be possible to estimate a per capita baseline for harm caused to vertebrate wild animals from an average plant-based diet. It will also be possible to identify which agricultural practices cause the highest mortality rates.

The output of this research project is a paper comprising the following:

  • An overview of existing research specifically addressing the harm caused to vertebrate wild animals because of crop cultivation.
  • A database detailing the population density changes (accounting for dislocation) in vertebrate wild animals before and after population control and cultivation activities for each of the selected crops in the United States.
  • An analysis of the findings and a discussion of alternatives to existing practices.

Methodology

  1. Review the literature on harm caused to wild animals as a result of agricultural practices.
    1. (Davis, 2003)
    2. (Matheny, 2003)
    3. (Lamey, 2007)
    4. (Middleton, 2009)
    5. (Archer, 2011)
  2. Select the top 1-3 calorie per hectare whole foods and the top 1-3 nutrient-dense foods for each macronutrient
    1. (“USDA Food Composition Database,” n.d.)
  3. Measure consumption requirement according to:
    1. Acceptable Macronutrient Distribution Range (Life Stage Vitamin A Vitamin C Vitamin D Vitamin E Vitamin K Group, n.d.):
      1. Protein: 10-35%
      2. Fat: 20-35%
      3. Carbohydrate: 45-65%
    2. Highest daily caloric range for males and females. (“EstimatedCalorieNeedsPerDayTable.pdf,” n.d.)

Note: This paper will not consider micronutrients as they are significantly more varied and complex to measure, and daily consumption requirements are small. This is based on the assumption that gram for gram we consume more to meet our daily macronutrient requirements than our daily micronutrient requirements.

  1. Examine cultivation activities for the selected crops.
    1. (“USDA ERS – Data Products,” n.d.)
    2. (“USDA – National Agricultural Statistics Service Homepage,” n.d.)
  2. Examine population control activities for the selected crops.
    1. (Joe E. Brooks and Lynwood A. Fiedler, n.d.)
    2. (“Rodenticides for Control of Norway Rats, Roof Rats and House Mice,” n.d.)
    3. (Epa, OCSPP, & OPP, 2013)
  3. Examine population density changes before and after agricultural practices.
    1. Cultivation activities
      1. International studies: the following papers include studies conducted outside the United States on the effects of various cultivation activities on the population densities of wild animals. The findings in these studies will be used to estimate similar effects on vertebrate wild animals in the United States based on the same cultivation activities and crops.
        1. (Tew & Macdonald, 1993)
        2. (Whisson, 1996)
        3. (Jacob & Hempel, 2003)
        4. (Jędrzejewski & Jędrzejewska, 1996)
        5. (Jacob, 2003)
        6. (Cavia et al., 2005)
      2. Studies in the United States: the following papers include studies conducted in various agricultural regions in the United States on the effects of cultivation activities on the population densities of wild animals. The findings in these studies will be used to estimate similar effects on vertebrate wild animals where data is unavailable.
        1. (Pinkert, Meerbeek, Scholten, & Jenks, 2002)
        2. (Cummings & Vessey, 1994)
        3. (Gary W. Witmer and Kurt C. VerCauteren, 2001)
        4. (Johnson, 1987)
        5. (Witmer, Sayler, Huggins, & Capelli, 2007)
        6. (Edge, Wolff, & Carey, 1995)
    2. Population control activities
      1. The following papers include studies on population control and “pest” management methods in United States agriculture. Their findings will be used to understand the mortality rates of vertebrate wild animals as a result of baiting, fumigation and trapping.
        1. (Gary Witmer, Nathan Snow, L. Humberg, and T. Salmon, 2009)
        2. (Gary W. Witmer, Patrick W. Burke, Will C. Pit, and Michael L. Avery, 2007)
        3. (Witmer, 2010)
        4. (Gary Witmer and Grant Singleton, 2010)
        5. (OTA, 1985)
        6. (“USDA – National Agricultural Statistics Service – Publications – Annual Statistics Book,” n.d.)
      2. The following is a comprehensive study of the relative humaneness of various population control methods. The findings will be used to understand the effects of baiting, fumigation and trapping on vertebrate wild animals.
        1. (Sharp & Saunders, n.d.)
  4. Discuss findings including an analysis of questions such as:
    1. How might population dynamics such as breeding periods affect mortality rates?
    2. Do nutrient-dense crops attract higher numbers of wild animals?
    3. Do the selected crops require a significantly larger land area than others?
    4. Do environmental conditions permit the cultivation of the selected crops to be replicated on a larger scale within the US?
    5. Which cultivation activities cause the most harm?
    6. Which cultivation activities can be substituted e.g. till versus no-till agriculture?
    7. How humane are rodenticides?
  5. Discussion of cost-effective and sustainable alternative agricultural practices that may minimise harm caused to wild animals such as:
    1. Reducing the population growth of “pests” rather than population control.
      1. (Bax & Thresher, 2009)
      2. New Zealand plans to manage the populations of some pests in agriculture through the Predator Free 2050 initiative (New Zealand Department of Conservation (DOC), n.d.).
      3. (Hobart, n.d.)
      4. (“The future – SenesTech, Inc,” n.d.)
    2. Habitat management such as reductions in vegetation height to encourage dispersal.
      1. (Gary Witmer and Grant Singleton, 2010)
      2. (Stenseth et al., n.d.)
    3. Vertical farms to reduce harm caused during tillage, sowing and harvesting.
      1. (“The Vertical Essay,” n.d.)
      2. (Banerjee & Adenaeuer, 2014)

Impact of our findings

A valid concern for proponents of reducing wild-animal suffering is the absence of viable large scale interventions. Our approach is to consider instances in which we already intervene in the lives of wild animals and discuss policies that reduce suffering caused by those interventions. Agricultural practices in the United States harm at least hundreds of millions of vertebrate wild animals each year, and humans have the capacity to prevent or at least minimise this. There are a number of promising outcomes as a result of the findings of this research project:

  1. Inform further research;
  2. Inform the advocacy of plant-based diet proponents;
  3. Contribute to the (currently very low) tractability of reducing wild-animal suffering advocacy; and
  4. Encourage institutional change by identifying cost-effective and sustainable policy proposals for the agricultural industry.

Informing further research

Current research on the harm caused to wild animals through crop cultivation can be characterised by its focus on the normative ethics of dietary choices as opposed to gathering comprehensive data. Davis, in his paper “The Least Harm Principle May Require That Humans Consume A Diet Containing Large Herbivores, Not A Vegan Diet” relies on two studies ((Tew & Macdonald, 1993) and (Nass, Hood, & Lindsey, 1971)) examining the mortality rate pre- and post-harvest in different regions (Oxfordshire and Hawaii, respectively) and on different crops (wheat and sugarcane, respectively) to estimate the total number of animals harmed by crop cultivation in the United States. Based on these estimates he concludes vegetarianism may cause more harm than a diet containing large herbivores reared on pasture-forage (Davis, 2003). The errors in his calculations are noted by Matheny who discovers that when considering animals killed per consumer, the crop production of soy and corn uses “less than half as many hectares as grass-fed dairy and one-tenth as many hectares as grass-fed beef to deliver the same amount of protein” (Matheny, 2003). Beyond this, the rest of Matheny’s paper focuses on the normative ethics of utilitarians. Lamey similarly notes the weakness of the data and focuses the rest of his paper on other harms caused to humans by beef production (Lamey, 2007). Middleton provides some of the most concrete data and analysis on the issue by considering the number of animals killed in animal agriculture to produce one million calories versus estimates of the number of animals killed to produce one million calories from harvesting crops. Whilst these papers establish a good foundation and raise important questions, they are far from conclusive. There are two important ways in which this research project advances this field of research:

  1. It uses the most comprehensive data available and a strong methodology to build reliable estimates; and
  2. It focuses on how to alleviate the harm caused to animals through crop cultivation.

Whilst the findings of this research project will not be conclusive, they will add value to the existing literature and pave the way for further research investigating both the effects of crop cultivation on wild animals and the policies to minimise those effects.

Informing plant-based diet advocacy

A key feature of the existing literature in this field is that it neglects to consider ways in which the suffering of wild animals in crop cultivation might be reduced. As noted above, those persuaded by Davis’ paper have not examined alternatives to reducing the suffering of field animals beyond adopting an omnivorous diet. For those who continue to advocate that a plant-based diet meets the principle of least harm, no further moral consideration is given to the fact that some harm is still inflicted as a direct result of our actions. This research project will inform and strengthen the advocacy of plant-based diet proponents in two ways.

Firstly, it provides guidance on how individuals can minimise the harm their diets cause by examining which crop cultivation methods cause the most harm, and which crops according to the macronutrient categories are least harmful. Plant-based advocates can use this information to adjust their diets accordingly. Secondly, it provides guidance on policies at an industrial level. Plant-based advocates can use this information to campaign for more humane practices in agriculture.

Supporting wild-animal suffering advocacy

Wild-animal suffering (WAS) is a highly neglected problem occurring on an enormous scale. However, it is a relatively intractable cause for which to advocate. This is because WAS is far removed from human experiences, scope insensitivity discourages action, status quo bias favors inaction, and there is an absence of viable solutions. This means one of the most valuable ways to act now is to “promote concern for wild animals in the hope that future generations—who are likely to have much more wealth, technology, and knowledge—will act rationally and humanely to reduce suffering in nature.” (“Wild Animal Suffering Research | Animal Charity Evaluators,” n.d.).

This research project presents a promising avenue through which to build the tractability of WAS by focusing on current practices, namely crop cultivation and population control activities, contributing to WAS which we have the existing capacity to change. Firstly, by examining current practices we highlight ways in which WAS is not as far removed from human experience and action as we might initially assume. Secondly, by examining our existing capacity to change these harmful activities we lower the barrier to developing viable solutions to reduce WAS.

Institutional change

Field animals cause a significant amount of damage to agricultural production on a global scale. In fact, rodents consuming or contaminating food production is said to be “one of the serious threats to adequate world food production” (Gary Witmer and Grant Singleton, 2010).  A report by the Food and Agriculture Organisation of the United Nations in 1982 estimated that rats destroyed more than 42 million tons of food globally with an estimated value of $30 billion (“The state of food and agriculture, 1982,” n.d.). In North America, house mice are responsible for 76% of the contamination to stored grain, while ground squirrels are responsible for 25% of the damage to wheat in fields (Gary Witmer and Grant Singleton, 2010). In 2000, Pimentel et al. estimated the total cost of damage by rats in the United States at $19 billion (Pimentel, Lach, Zuniga, & Morrison, 2000). With such a significant impact on livelihoods and food security, Integrated Pest Management (IPM) techniques to reduce the populations of wild animals in crop fields are vitally important.

There are strong economic incentives to find cost-effective and sustainable reductions to wild animal populations in fields. There is an equally strong ethical incentive for proponents of reducing wild-animal suffering to find humane solutions to reductions in wild animal populations in fields. This research project unites these incentives by examining policy proposals such as:

  1. Reductions in population growth through gene drives and/or sterilisation which reduces the need for lethal population control through rodenticides and reduces the population density of field animals;
  2. Habitat management which encourages dispersal to natural vegetation by reducing access to shelter and food for field animals; and
  3. Alternative farming practices such as vertical farms which reduce damage caused to crops by field animals and harm caused to field animals through cultivation activities like tillage, seeding and harvesting.

Finding joint solutions is one of the most promising ways to both raise awareness and concern for wild-animal suffering and influence change on an institutional level.

Limitations

  1. The absence of definitive data on mortality rates of vertebrate animals as a result of cultivation activities. Data will be gathered based on estimates and small sample size studies.
  2. Measuring changes in population densities won’t accurately account for the proportion of mortality rates versus dislocation. Studies estimate dislocation rates based on increases in population densities in surrounding regions or by tracking animals in small sample studies.
  3. Selecting crops based on macronutrient density doesn’t distinguish between high density micronutrient foods and nutritionally dense foods i.e., food that contains lower primary macronutrients per gram, but more micronutrients.
  4. Selecting crops based on macronutrient density doesn’t account for the harm caused to vertebrate wild animals as a result of crops grown to meet micronutrient requirements.
  5. The absence of comprehensive data on all vertebrate wild animals harmed through agricultural practices. The data will focus on the vertebrate animals with the highest densities per hectare of the selected crops.
  6. Cultivation methods for the same crops may vary in different regions which means generalisations are imperfect.
  7. This study does not account for indirect effects such as pesticide use on vertebrate wild animals.
  8. This study does not account for indirect effects on invertebrates in favouring nutrient-dense and high-yield crops over others.

Project timeline

 TimeProgressExpenseAmount
240 hours (6 weeks)

This estimate is based on the average time taken to complete similar WAS research papers.
Literature researchPaid researcher (Persis Eskander) at $20 / hour$4800
80 hoursReport completion and publicationPaid researcher (Persis Eskander) at $20 / hour$1600
Total320 hours
$6400

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