The influence of industrial livestock on biodiversity loss is rarely discussed. When talking to people about biodiversity, many relate the loss of ecosystems to the growth of urban sprawl or pollution generated by human settlements and manufacturing industries. However, few people know the implications of cattle ranching in terms of land use, even if agriculture is identified as an activity that devastates forest areas, believing that a transition to diets that contain more plant-based products would be worse for biodiversity.
Although cattle ranching is a growing productive activity in the area it occupies, its negative effects on the soil are becoming increasingly evident. It is an important livestock practice because it produces high-quality protein food; however, it is one of the anthropogenic activities that causes the most damage to ecosystems and biodiversity. As the livestock sector develops, its land requirements grow and the sector undergoes a geographic transition involving changes in land-use intensity and geographic distribution patterns.
Effects of Extensive Land Use by Cattle Ranching
Livestock farming occupies 30% of the planet’s ice-free surface (some say that in recent years it has reached 45%) and in several places, it is the main source of soil contamination and the emission of nutrients, organic matter, pathogens, and drug residues into rivers, lakes and coastal areas. Animals and their excreta emit gasses that contribute to climate change. Livestock farming shapes entire landscapes and reduces natural habitat with its demand for land for the production of pasture, forage, feed grains, and other agricultural inputs involved in feeding livestock (,Thornton et al., 2011; ,Walsh, 2013).
Livestock occupies 78% of agricultural land and about 33% of cropland. Although intensive “landless” systems are responsible for most of the growth in the sector, their influence on cropland is substantial and the problems associated with livestock production cannot be fully understood without including the crop agricultural sector in the analysis.
This industry pollutes since poor handling and lack of treatment of animal feces and urine is a major factor in soil and water contamination, and a source of infectious diseases for humans. In addition, nitrates, a chemical from the massive use of synthetic fertilizers and the huge amount of excrement generated by industrial livestock, seep into the ground, poisoning the soil and its aquifers (,EPA, 2013), which consequently reaches the oceans, which has led to an increase in dead zones, i.e., low oxygenation, in the world’s seas (,Paine, 2012; ,NOS, 2021).
Herds cause large-scale soil damage at the same time, with about 20 percent of grasslands degraded through overgrazing, compaction, and erosion. This figure is even higher in drylands, where misguided policies and inadequate livestock management have contributed to the advance of desertification.
Biodiversity Loss Due to Habitat Loss
From the perspective of geographic transition, livestock is the main user of land; it occupies more than 3.9 billion hectares. The intensity of use of this resource is extremely variable. Of the 3.9 billion hectares, 500 billion are intensively cultivated, 1.4 billion are relatively high productivity pastures, and the remaining 2 billion hectares are extensive pastures of relatively low productivity.
The conversion of forest areas to induced grasslands and croplands, mainly for soybeans and corn, are the main drivers of deforestation and therefore the loss of biodiversity. It is important to remember that up to 70% of the world’s grain production is used to feed food animals.
Deforestation and the advance of the agricultural frontier are closely linked. It is common for the slashing and burning of forests to be one of the first processes in the expansion of livestock and agriculture, initially at low intensity, and then shifting towards more intensive practices. This deforestation displaces animal species and eliminates plant species that proliferated in the area (,Hogan, 2014), turning them into pests or now invasive species that affect crops or animal production. Mainly, carnivorous animals are a threat to livestock farmers, since, being displaced, they will seek to feed on those animals in corrals; livestock farmers, therefore, will put their efforts into eliminating predators that affect their production, as is the case with wolves, jaguars, leopards, lions, etc.
Our current food system has serious collateral effects for other animals: 60% of the planet’s mammals, birds, fish, and reptiles have disappeared from our planet since the 1970s, until 2014, all as a result of human activity. A loss of about 100 000 species per year has also been estimated (,CU, 2012). This phenomenon is known today as the sixth mass extinction, a process in which wildlife is decimated at up to 1,000 times the natural rate (,EPA, 2004; ,Ceballos et al., 2015).
Our diets (particularly the habit of eating animal products) are behind this imbalance. Currently, 70% of all avian biomass on the planet is food birds and 60% of mammals are livestock, primarily cows and pigs, estimated to occupy up to 5 acres per individual (,McBride & Mathews, 2011), 36% are humans and just 4% are wild animals.
Livestock is the largest user of land resources in the world, with grazing areas and plantations used for feed production accounting for nearly 80% of all agricultural land. Food crops use one-third of the arable area, while grazing land is equivalent to 26% of the ice-free land area. Another considerable part is used for crops, mostly to feed animals.
These numbers are more than enough evidence to prove that giving up animal products is imperative to maintain a healthy ecological balance for all living beings on the planet, of which we are part and of which we have a fundamental role.