Statistical invisibility of working equids in Mexico: Dissecting the gap between global diagnostics and official data (1970-2022).

This study reveals that despite a 76.5% overall decline in Mexico's equine population since 1970 and a massive 710.8% overestimation in international data, working equids have experienced a paradoxical resurgence driven by economic necessity, underscoring their critical yet statistically invisible role in the country's small-scale agricultural sector.

The Gist

The Big Picture: The "Ghost" Animals of Mexico

Imagine Mexico's countryside as a giant, bustling kitchen. For decades, the world has been watching this kitchen through a telescope, trying to count the chefs and the tools they use. But there's a massive problem: The telescope is broken.

This paper argues that international organizations (like the UN's FAO) are looking at Mexico's working animals (horses, donkeys, and mules) and seeing a completely different reality than what is actually happening on the ground. They are counting "ghosts"—numbers that don't exist—while the real animals are quietly struggling to survive.

Here is the story broken down into three main acts:

---

Act 1: The Great Vanishing Act (But with a Twist)

The Story:
Between 1970 and 2022, the total number of horses, donkeys, and mules in Mexico dropped by 76%. It's like a massive crowd of people leaving a stadium; the seats are mostly empty now.

The Twist (The "Modernization Paradox"):
You might think, "Oh, so everyone just bought tractors and stopped using animals." That's what the world thinks happened. But the data tells a different story.

While the total number of animals dropped, the percentage of animals actually working (pulling plows, carrying firewood, transporting goods) skyrocketed.

• In 2007: Only 44% of the animals were working.
• In 2022: That number jumped to 81%.

The Analogy:
Imagine a gym. In 1970, the gym was full of people, but half of them were just sitting on the benches chatting (pets or leisure animals). By 2022, the gym is half-empty, but almost everyone left is lifting heavy weights.

Why? Because the "easy" animals (pets or those used for leisure) disappeared, but the animals that are essential for survival are still there. Small farmers in the mountains can't afford tractors or gas. They need these animals to eat. It's not a sign of "backwardness"; it's a sign of resilience. They are the "rescue team" that shows up when the fancy machinery fails.

---

Act 2: The Three Musketeers (Who Are Dying at Different Rates)

The paper looks at three specific types of working animals, and they are having very different experiences:

1. The Horses (The Comeback Kids):

   • Status: They hit a low point in 2007 but have been making a strong comeback since then. Their numbers are actually growing again (+3.7% per year).
   • Why: They are versatile and tough. Farmers are realizing they need them more than ever.

2. The Donkeys (The Silent Sufferers):

   • Status: They have been decimated. Their numbers dropped by 87% since 1970.
   • The Crisis: In many states, they are on the brink of local extinction. They are disappearing faster than the horses.

3. The Mules (The Vanishing Act):

   • Status: The worst hit. Their numbers dropped by 88%.
   • The Crisis: In some places (like Quintana Roo), they are almost gone. It's like a species that has lost its entire neighborhood.

The Analogy:
Think of these animals as three runners in a marathon.

• The Horse tripped, fell, got up, and is now sprinting toward the finish line.
• The Donkey and Mule are running, but they are being chased by a giant vacuum cleaner (economic pressure and lack of support) that is sucking them out of the race one by one.

---

Act 3: The "Ghost" Numbers (The Big Lie)

This is the most shocking part of the paper.

• The International View (FAOSTAT): The global database says Mexico has about 13 million equids.
• The Real View (Mexican Census): The actual count is only 1.6 million.

The Discrepancy:
The international numbers are 710% too high. They are overestimating the population by 11.3 million animals.

The Analogy:
Imagine you are planning a party.

• The International Planner looks at a map and says, "There are 13 million people in this city! We need 13 million pizzas!"
• The Local Host looks out the window and says, "Actually, there are only 1.6 million people here. If you send 13 million pizzas, we will have a mountain of rotting food, and the real people will still be hungry because the resources were wasted on ghosts."

Why does this happen?
The international models assume a neat, organized system where every animal is registered. But in Mexico, the reality is messy.

• Many animals are "invisible" to the system because they are small-scale farmers' tools, not "commodities" like cows raised for meat.
• Meanwhile, a huge number of horses are being imported from the US, slaughtered for meat, and exported. These animals move through the system like shadows—they appear in meat statistics but vanish from population counts.

The Bottom Line: Why Should We Care?

This isn't just about counting animals. It's about human survival.

• The Invisible Problem: Because the world thinks there are millions more animals than there really are, they think everything is "fine." They don't send help because they think the population is stable.
• The Real Danger: In reality, the animals that keep rural families alive (especially donkeys and mules) are disappearing. When they vanish, the farmers lose their ability to farm, transport water, and get food to market.
• The Solution: We need to stop looking at the "ghost numbers" and start looking at the real data. We need to recognize these animals not as "old-fashioned relics," but as essential infrastructure for food security and poverty reduction.

In short: The world is looking at a map of a city that doesn't exist, while the real city is struggling to keep its lights on. This paper is the flashlight showing us where the real people (and animals) actually are.

Technical Summary

1. Problem Statement

Working equids (horses, donkeys, and mules) are critical to Mexico's small-scale agricultural sector, supporting approximately 71.2% of the country's Agricultural Production Units (APUs), particularly in marginalized and topographically complex regions. Despite their role in food security and rural livelihoods, these animals face "statistical invisibility."

• Institutional Bias: They are often classified as "non-productive" because they do not yield direct commodities (meat/milk), leading to exclusion from national budgets and health programs.
• Data Discrepancy: There is a profound disconnect between "bottom-up" national census data and "top-down" international estimates (FAOSTAT). International models often rely on stagnant dogmas (e.g., assuming 90% of global equids are working animals) that fail to reflect the specific, evolving reality of the Mexican agricultural landscape.
• Consequence: This statistical gap leads to inaccurate welfare diagnoses, inefficient policy design, and a lack of evidence-based veterinary support for the ~500,000 APUs dependent on animal traction.

2. Methodology

The study employed a retrospective analysis of official Mexican data spanning 52 years (1970–2022).

• Data Sources:
  • Primary: National Agricultural Censuses conducted by the National Institute of Statistics, Geography, and Informatics (INEGI) for the years 1970, 1991, 2007, and 2022.
  • Secondary: Data from the Agri-food and Fisheries Information Service (SIAP) and the Ministry of Agriculture and Rural Development (SADER).
  • Comparative: FAOSTAT database estimates for 2022.
• Statistical Analysis:
  • Population Trends: Calculated using the Average Annual Variation Rate (AAVR) based on a geometric growth model to account for unequal census intervals.
  • Conservation Criteria: An adaptation of the IUCN Red List criteria was applied to the 2007–2022 period to classify the severity of population declines in federal entities (Levels 1–4, ranging from "Warning" to "Critical/Crisis").
  • Discrepancy Analysis: Direct comparison of INEGI census figures against FAOSTAT estimates to quantify reporting errors.
• Geospatial Analysis: Distribution maps were generated using ArcGIS to visualize regional concentrations and vulnerabilities.

3. Key Results

A. Long-Term Population Dynamics (1970–2022)

• Total Decline: The total equine population in Mexico decreased by 76.5%, falling from 6.8 million (1970) to 1.6 million (2022).
• The "Modernization Paradox": While the total population plummeted, the proportion of animals used specifically for work reached a historical peak of 81% in 2022 (up from 44% in 2007). This indicates that as mechanization reduced the total herd, the remaining animals are almost exclusively those essential for labor.
• Species Divergence:
  • Working Horses: Experienced a 37% recovery between 2007 and 2022 (AAVR +3.71%), transitioning from a decline to growth.
  • Working Donkeys & Mules: Suffered catastrophic declines of 87.7% and 88%, respectively, since 1970. While their rate of decline slowed slightly in the last 15 years, they remain in a state of continuous reduction.

B. Regional Vulnerability (2007–2022)

• Horses: Showed resilience, with population increases in 31 out of 32 federal entities.
• Donkeys: Declined in 21 entities; 13 reached Level 2 (Significant decline) and 2 reached Level 3 (Extinction risk).
• Mules: Faced the most severe crisis, declining in 23 entities.
  • Level 3 (Alarming): 6 states.
  • Level 4 (Critical): Quintana Roo, where the mule population has effectively collapsed.

C. Statistical Invisibility & Data Discrepancy

• The Gap: A staggering 710.8% discrepancy exists between international and national data for 2022.
  • FAOSTAT Estimate: ~12.9 million equids.
  • INEGI Census: ~1.6 million equids.
  • Overestimation: International records overestimate the Mexican population by 11.3 million animals.
• The "Invisible" Meat Market: The study notes that while working equids are "invisible" to agricultural budgets, Mexico processes ~400,000 equids annually for meat (mostly imported from the US). These animals bypass census tracking but appear in slaughter statistics, further distorting the perception of the living working population.

4. Key Contributions

1. Evidence of the "Resilience of Necessity": The study refutes the narrative that working equids are a relic of backwardness. Instead, it proves they are a resilient, necessary adaptation for smallholders facing high fuel costs, lack of credit, and difficult terrain (e.g., the Trans-Mexican Volcanic Belt).
2. Quantification of Statistical Invisibility: It provides concrete data demonstrating that global databases (FAOSTAT) are fundamentally flawed regarding Mexico, masking the true scale of the crisis for donkeys and mules.
3. Refined Conservation Metrics: By adapting IUCN criteria to a 15-year agricultural census window, the study identifies specific federal entities facing imminent regional extinction of working equid populations.
4. Policy Diagnosis: It highlights that the "invisibility" is not a lack of data, but a failure of data integration and classification, leading to a disconnect between veterinary education, public health, and rural reality.

5. Significance and Implications

• Sustainable Development Goals (SDGs): The persistence of working equids is directly linked to SDG 1 (No Poverty) and SDG 2 (Zero Hunger). Ignoring their status threatens the livelihoods of nearly 500,000 small-scale farming units.
• Policy Reform: The findings call for an urgent shift from "statistical invisibility" to institutional recognition. This includes:
  • Integrating equid welfare into national agricultural frameworks.
  • Developing specialized veterinary services for working equids.
  • Correcting global databases to reflect verified field data to prevent misinformed international interventions.
• One Welfare Framework: The study reinforces the "One Welfare" concept, demonstrating that the well-being of working equids is inextricably linked to the quality of life, economic stability, and food security of rural human populations.

Conclusion: The paper concludes that while working horses are showing signs of recovery due to economic necessity, donkeys and mules are facing regional extinction. Correcting the massive statistical overestimation in global records is a prerequisite for designing effective policies to support rural sustainability and prevent the collapse of Mexico's small-scale agricultural sector.