A new scientific approach led by researchers from the University of Berkeley suggests that cows can be an ecological tool to reduce fires, restore biodiversity, and store carbon in soils.
The proposal challenges the dominant narrative that points to them as one of the main contributors to global warming.
The debate: methane vs. grassland management
Criticism of livestock farming has a solid basis: methane is a very potent greenhouse gas, capable of trapping up to 80 times more heat than CO₂ over a 20-year horizon. In California, approximately half of methane emissions come from livestock, mainly from burps and manure.
However, grassland ecologist Lynn Huntsinger warns that this figure only shows part of the story. When emissions are adjusted to CO₂ equivalents, all agriculture accounts for about 8% of the state’s emissions. Additionally, the California rangelands, which cover more than half of the territory, historically evolved with herbivores and periodic disturbances.
The uncomfortable question is another: what if the problem is not the number of cows, but the lack of well-managed grazing in the right places?
Cows as an ecological tool
Researchers like Huntsinger use controlled grazing to:
- Reduce invasive species that displace native flora.
- Protect watersheds.
- Decrease the load of plant fuel, reducing the risk of fires.
In increasingly dry and unstable landscapes, cows can play a corrective role against decades of neglect and poor management. “Well-managed, they promote biodiversity and reduce the likelihood of fires starting and spreading,” says Huntsinger.
A 2022 study estimated that livestock removed about 5.4 billion kilos of flammable biomass in California grasslands. Reducing fires also means reducing emissions, as in 2020 large fires contributed almost a quarter of the state’s total emissions.
Biodiversity and soil carbon
Cows, by consuming invasive species like wild oats or medusahead, help control their spread. These non-native plants have transformed ecosystems, reducing habitats for birds and pollinators. Livestock, by preferring them, helps balance the landscape.
Moreover, the hooves of livestock perform an ecological function: they disturb the soil and stimulate the germination of certain native flowers. Moderate grazing also favors root growth, increasing the carbon stored in the soil.
Challenges and solutions
Extensive livestock farming faces difficulties: droughts, urban pressure, and rising costs. Organizations like the California Rangeland Trust promote conservation easements to protect land from speculation and ensure responsible management.
Regarding methane, California seeks to reduce its emissions by 40% by 2030. To this end, it incentivizes anaerobic digesters that convert the gas into biomethane for transportation. Although the measure generates debate, studies do not show a deliberate increase in production due to these aids.
More complex is the methane from burps. Experimental research is working on modifying the rumen microbiome through red algae and genetic editing techniques, aiming to permanently reduce emissions in each animal.
The debate about cows does not admit simple answers. Their environmental impact depends on how, where, and for what they are managed. Eliminating livestock abruptly could increase fires and biodiversity loss, while maintaining intensive models without changes is also unsustainable.
Berkeley’s proposal opens a key discussion: cows, far from being just a climate problem, can become allies of ecological resilience if integrated into conservation strategies and responsible landscape management.
