Most wild coffee plants are at risk of going extinct

The death knell for wild coffee has been sounded before, much to the chagrin of coffee aficionados, but a team of scientists is sounding the alarm again.

Researchers at Kew Gardens in the United Kingdom estimate that almost two-thirds, or 60%, of the 124 known coffee species at risk of extinction. In some areas, such as Madagascar and around the Indian Ocean, as many as 71% of coffee species are at risk. Of the 75 coffee species facing extinction worldwide, 13 species can be classed as critically endangered, 40 as endangered, and 22 as vulnerable, they say.

The culprits behind the plight of wild coffee plants are the usual suspects with habitat loss and climate change being the primary causes. Rising temperatures may harm heat-sensitive coffee plants, including hugely popular Arabica plants that are beloved the world over for their rich aroma. Arabica is cultivated widely in the famous “Bean Belt,” which girds the tropics and encompasses Brazil, Ethiopia, and Vietnam, among other countries.

All the world’s coffee comes from just two cultivated species: arabica and robusta. Arabica accounts for as much as 70% of all coffee sales worldwide. Arabica grows well at around 23 degrees Celsius but suffers at higher temperatures. And local temperatures at several places where it is cultivated have already shot by up to 1.3 degrees Celsius.

Tanzania, where coffee production is a major part of the local economy, has seen coffee yields almost halve already over the past half century. Coffee crops, which are routinely cultivated on hillsides, are also at increasing risk of succumbing to new diseases like coffee rust and to pests like a beetle called the coffee berry borer.

Habitat loss is another concern. In Ethiopia, the homeland of some of the world’s best coffees, the land area where Arabica currently grows could shrivel by up 85% in a little over a half century. That would devastate the economy of the country, which is Africa’s biggest coffee producer exporting $1 billion worth of coffee each year in an industry that employs 15 million people.

“Overall, the fact that the extinction risk across all coffee species was so high — nearly 60 percent — that’s way above normal extinction risk figures for plants,” says Aaron Davis, head of coffee research at Kew Gardens who was a lead author of the study published in Science Advances. “It’s up there with the most endangered plant groups.”

Although the two cultivated coffee species are still doing well, wild coffee species aren’t. They are facing several threats, including diseases that could wipe them out. This worries coffee experts because the loss of wild coffee species could greatly reduce the genetic diversity of cultivated coffee plants, which is what has happened with other popular crops such as bananas.

“Among the coffee species threatened with extinction are those that have potential to be used to breed and develop the coffees of the future, including those resistant to disease and capable of withstanding worsening climatic conditions,” says Davis. “The use and development of wild coffee resources could be key to the long-term sustainability of the coffee sector,” he adds. “Targeted action is urgently required in specific tropical countries, particularly in Africa, to protect the future of coffee.”

To protect beleaguered coffee plants in the wild, their natural environments will have to be protected too. Forests, that is.