Beef production leads to water scarcity and imperils fish: researchers

Cows stand in stalls in a barn

The study shows that one-quarter of all the water consumed in the entire U.S. goes to irrigating cattle-feed crops.

2020 March – Beef and dairy production is the leading cause of river and stream depletion in the Western United States, which in turn leads to water scarcity and threatens fish populations, according to a paper co-authored by a UVic researcher.

An international team of researchers – including Tara Troy of UVic Civil Engineering – studied the effects of cattle-feed irrigation on streamflow,the flow of water in streams, rivers and other channels. The paper has been published in the prestigious Nature Sustainability.

“Beef and dairy production have a large water footprint, both because of the needs of the cattle themselves but primarily because animal feed is often irrigated,” Troy explains. “While the study focuses on the Western U.S., it should be a concern for any nation that produces beef with irrigated cattle feed.”

The study shows that more than one-quarter of Western U.S. rivers nearly or completely dry up during drought years and that cattle-feed irrigation is the leading cause. Not only is this water scarcity posing severe risks of water shortages for many communities, it is also linked to nearly 700 instances of fish species extirpations – localized extinction – from watersheds and more than 50 species being at elevated risk of extinction.

“Our study shows that large cities in the Western U.S. – such as Los Angeles, Denver, Portland and Seattle – are the leading consumption centres of the beef responsible for river drying,” said Troy. “This highlights how our decisions in one location can impact the environment of a region far away.”

One-quarter of all the water consumed in the entire U.S. goes to irrigating cattle-feed crops. For the Western U.S., it’s one-third and in the Colorado River basin, it’s more than half.

The paper assesses opportunities for alleviating water scarcity by reducing cattle-feed production, finding that temporary, rotational fallowing of irrigated feed crops can markedly reduce water shortage risks and improve ecological sustainability. Long-term water security and river ecosystem health will ultimately require Americans to consume less beef that depends on irrigated feed crops.

Read the complete paper at Nature.com and a related blog on the publication’s sustainability forum.

Photo by freestocks.org

2020Mar03 AT