Sustainable Happy Hour
As shelter-in-place orders took effect across the country in March, trends in consumer activity have been closely monitored. Among the bestselling items these days are spirits like tequila and gin, with sales jumping 75 percent compared to last year. While Americans stock up on liquor, certain bats are being blamed as one source of the virus behind COVID-19. Few praise other bats for their role in producing the tequila that makes one of the most popular, do-it-yourself cocktails - the margarita.
On hot summer evenings in the 1990s, my parents, homemade margaritas in hand, would walk us over to check the status of a neighbor’s garden. In the small, isolated desert communities surrounding Big Bend National Park in far west Texas where I grew up, a neighbor’s blooming agave, or “century plant”, was an occasion. Because everybody’s yard contained at least one agave, witnessing a bloom was always a certainty.
Century plants grow wild all over southwest Texas. The leaves of the plants can be broader than a large man’s hand and five feet tall, taking up a plot ten feet across. Their name is a misnomer. They live for seven to fifty years, not a hundred. But they only bloom once, right at the end of their lives, and their bloom is so dazzling and precious that, as children, the fable was that it happened only once in a hundred years. Hence, “century plant”. When the plant is ready to flower, an asparagus-looking dagger with the diameter of a telephone pole emerges from its center. As the stalk reaches an astonishing thirty feet tall, it unfurls its branches laden with bright yellow blossoms, a dazzling display to marvel at against the backdrop of a dusty town and endless sky.
A Mexican long-nosed bat. Photo by Steve Buchmann.
No creature appreciates those blossoms more than the Mexican long-nosed bat. While many bats feed on insects, the Mexican long-nosed bat’s diet consists exclusively of agave pollen and nectar. I knew a colony of females and their young roosted deep in a cave in the national park, coming out to feed when the agave flowers opened at night. I knew the margaritas clinking around in my parents’ to-go cups had a relationship to the plant we admired. What I didn’t understand was that the bats, the agaves, and the margaritas were intrinsically linked. Other than the occasional misguided bat flying through an open window at night, I rarely saw them.
The Mexican long-nosed bat has a single, migratory population that spends its winters mating in one particular cave, Cueva del Diablo, in the central Mexican state of Morelos. This is the only time of year that males and females congregate. When the young are strong enough to fly in the spring, they begin the journey northward with their mothers, following the “nectar corridor” of blooming agave into northern Mexico and the southern United States while the males stay behind in Morelos. As the females and their young consume the nectar, they also inadvertently eat and transport the plant’s pollen on their fur, making the bats a vital pollinator of the agaves. The agaves provide the food necessary for the bats to survive their migration and, in turn, the bats distribute the agave’s pollen, ensuring its survival. It’s a tale of symbiosis as old as time.
Enter tequila. Tequila is to the state of Jalisco, Mexico as Champagne is to the province Champagne, France - if it’s not from there, it’s not the real thing. In the 16th century, the Indigenous wisdom of the agave mixed with the innovation of the Spaniards created a distillation process that produced the powerful spirit we drink today. For centuries, the plant was cultivated and sold as family-owned brands. Today, most well-known tequilas are owned and distributed by large multinational corporations.
As the agave prepares to flower, it concentrates its sugars in its center, or piña. If left untouched, this sugar would eventually be sent up its stalk and into its flowers for the bats to feed on. For tequila producers, however, the optimal time to harvest is when the sugar is still in the piña. By not allowing the plant to flower and sexually reproduce on its own, growers instead rely on fields of agave clones, an efficient method for quality control and precise timing, but also a sometimes disastrous technique due to the lack of genetic diversity. Because the plants are all copies of themselves, they are susceptible to the same dangers like pests or disease. These monocultures have the most devastating consequences, though, for the bats.
By far the biggest tequila market is the United States, buying up 80 percent of exports. American demand for tequila has grown 158 percent since 2002. At the beginning of April, the president of the National Tequila Regulatory Chamber, Rodolfo González, quelled worries that tequila production would slow or stop because of the coronavirus. González, a tequila distiller himself, predicted growth rates between 4 to 5 percent in the tequila sector despite the pandemic.
To keep up with demand, producers rely solely on vast fields of cloned agaves, eradicating wild agave species and harvesting the clones before they are able to flower. If the bats can’t find and eat the nectar, they die. As of their last assessment in 2015 by the International Union for Conservation of Nature, Mexican long-nosed bats are considered endangered. In the last ten years alone their population has declined by over 50 percent.
Rodrigo Medellín. Photo by Anand Varma.
Mexican ecologist and biologist Rodrigo Medellín, affectionately referred to by many as “The Bat Man”, foresaw the calamity awaiting both the bats and the tequila industry decades ago. He knew a productive and resistant field of agaves required genetic diversity via pollination that only the bats could provide, and that the bats needed agaves to flower to avoid extinction. For years he has implored growers and buyers to consider the connection between the bats and agaves, advocating for allowing a fraction of the crops to bloom and be pollinated. In 2010, the Tequila Interchange Project was formed to encourage sustainable practices in the tequila industry, and in 2014, Dr. Medellín partnered with them to form the Bat Friendly Tequila and Mezcal Project, “an alliance of producers, scientists, and bartenders that advocates the preservation of traditional agave farming, naturally pollinated agave, and other sustainable, environmentally friendly practices.”
For the towns and cities of the American southwest that prize their neighborhood century plants, and for all Americans perfecting their margarita-making skills as they ride out the lockdown, sourcing and supporting bat-friendly tequilas is imperative to ensuring the resiliency of the tequila market, the livelihoods of the bats, and the continuous bloom of the agaves. Bat Friendly contains lists of brands that meet this sustainable criteria. We can ask our local liquor suppliers to stock bat-friendly tequilas, and perhaps occasionally donate what we would spend on our pre-pandemic cocktails to this initiative. The stunning bloom of the century plant is more than a display for us to admire. It’s a symbol of thousands of years of coevolution between bats and agaves. The next time you sip tequila, let it be a reminder of our responsibility to protect this fragile relationship.