Restoring a 1,200-Kilometer Nectar Corridor for Endangered Migratory Bats

Three species of nectar-feeding bats, including the endangered Mexican long-nosed bat, migrate each spring along a 1,200-kilometer chain of flowering agaves between central Mexico and the U.S. Southwest. Pregnant females rely on the nectar to fuel the journey to maternity roosts, and in return they pollinate the agaves that sustain the corridor. The Mexican long-nosed bat has declined roughly 50 percent over recent decades and was listed as endangered in 1988.

Bat Conservation International launched the Agave Restoration Initiative in 2018 with the Northeast Mexico Agave Restoration Network, a coalition of nonprofits, ejido communities, private ranchers, government agencies, companies, and universities. Kristen Lear directs the effort, which operates 26 nurseries that propagate agaves alongside vegetables and medicinal plants to integrate conservation with rural livelihoods. Fifteen long-term agreements with Mexican ejidos protect degraded land along the corridor, leaving agaves undisturbed so they can flower.

A central constraint is the agave's biology: each plant can take up to ten years to reach flowering age. Agaves planted today will not provide nectar until the mid-2030s at the earliest, while the bat population continues to shrink. The initiative has so far restored 5,886 hectares and planted over 185,000 agaves since 2018.

Recent environmental DNA sampling and community science surveys have detected Mexican long-nosed bats in a new state and documented a roughly 160-kilometer northward range shift. Researchers in New Mexico's Bootheel region link the shift to drought reducing agave flowering in traditional habitat, forcing bats to travel farther north where plants are less drought-stressed. An additional 30 miles can add a full night to a bat's migratory journey, a significant energetic cost for an animal operating near its physiological limits.

The related lesser long-nosed bat offers a precedent: it grew from roughly 1,000 known individuals in 1988 to an estimated 200,000 by 2024 after legal protection of its roosting caves. That recovery took 36 years and required roost protection as much as habitat restoration, underscoring that agave planting alone will not save the Mexican long-nosed bat without complementary measures against poaching, cave disturbance, and habitat loss.

Threats persist alongside restoration. Rising demand for bacanora, a Sonoran distilled spirit, leads producers to harvest agaves before they flower. Urban development in Arizona and Sonora continues to remove agave habitat even as new stands are planted elsewhere along the corridor.

The initiative's 2030 goal is 500,000 agaves planted and 95,000 hectares restored and protected, more than fifteen times the current footprint. More than 100 partners now participate in DNA sampling and agave patch surveys to target planting toward areas bats are actually using, rather than relying on raw hectare counts. Success will depend less on total agaves planted than on whether enough mature into flowering habitat before the remaining bat population runs out of time.