Near the imposing border wall, accompanied by a U.S. Border Patrol vehicle, botanist Sula Vanderplank detected a quail in the scrub announcing “chi-ca-go,” a cry signaling separation from its mate or group.
Then, there was quiet.
A quail on the Mexican side responded, setting off a poignant exchange of calls, highlighting the divide created by the man-made barrier.
Vanderplank was part of a group of botanists and citizen scientists participating in the Border Bioblitz near the Mexican community of Jacumé, roughly 60 miles (100 kilometers) east of Tijuana.
Around 1,000 volunteers, equipped with the iNaturalist app on their smartphones, aimed to document as many species as possible along the U.S.-Mexico border in May. By uploading photos to the app, they helped identify various species and record the coordinates of their findings.
The goal is for this data to lead to enhanced protection for the region’s diverse natural environment, which often gets overshadowed by reports of drug trafficking and illegal immigration.
Recently, Bioblitz volunteers examined a vibrant yellow expanse of blooming common Goldfields, stark against the severe steel bollards of the border wall crowned with coils of razor wire. Some navigated around remnants of human presence like empty water jugs, a grey hoodie, and discarded tuna cans under the branches of native plants like the Tecate Cypress.
“There’s an incredible amount of biodiversity here that’s traditionally been overlooked,” said Vanderplank, who is associated with the binational program Baja Rare.
This initiative began as a response to former President Donald Trump’s administration constructing hundreds of miles of border walls, which destroyed countless saguaro cactuses in Arizona and cut through Baja California’s biodiversity hotspot.
“When construction of the border wall started, we realized how scant our concrete data was, particularly regarding plants and smaller organisms,” Vanderplank noted. “We’re unaware of the full extent of what we could lose.”
Since then, numerous efforts have been made to document the borderland’s flora and fauna as they face threats from climate change, habitat destruction, pollution, and development. A 2019 estimate warned that one million plant and animal species are at risk of extinction within decades, a rate 1,000 times greater than what would naturally be expected.
In October, the United Nations is set to host a major meeting in Colombia with signatories to the Convention on Biological Diversity. The aim is to commit to protecting 30% of crucial land, freshwater, and ocean areas for biodiversity by 2030, an initiative known as 30 by 30. Representatives from nearly 200 countries will discuss how they plan to meet conservation targets set in 2022.
Currently, only 17% of land and 10% of marine areas are under protection.
The Baja California peninsula, adjacent to California and home to one of Mexico’s most violent cities, Tijuana, boasts over 4,000 plant species, with a quarter endemic to the area and at least 400 considered rare with minimal to no protection.
Species that are extinct or endangered in the U.S., such as the California red-legged frog, thrive south of the border, with specimens used to bolster dwindling populations.
However, the region’s crime rate deters many U.S. scientists from crossing the border, and Mexico’s restrictions on botanical permits and seed collection further limit research, according to scientists.
Bioblitz organizers coordinate with local communities and ensure visits only to areas deemed safe.
“The violence necessitates extreme caution,” said Jon Rebman, a curator of botany at the San Diego Natural History Museum, who has identified 33 new plants from the southern California and Baja California region.
“It’s daunting, but these are the areas where we most need more data because there’s scant protection on the southern side,” he added.
Using the museum’s collection, Rebman identified 15 plant species endemic to Baja California that haven’t been seen since nearly a century ago. He assembled a binational team to locate them. So far, they have found 11.
Rebman also discovered two new plant species in 2021 in a canyon off a Tijuana highway: a new species, Astragalus tijuanensis, and a new variety of Astragalus brauntonii named lativexillum.
“I was concerned they might become extinct before we even named them,” Rebman explained. “That shows the kind of area we’re dealing with.”
Tijuana-based botanist Mariana Fernandez of Expediciones Botánicas regularly checks on these plants. Working with Rebman, she advocates for Baja California to implement stronger protections for its native flora. Currently, only a small number are on Mexico’s federal protection list.
She hopes the state will intervene, while she also works to garner support by taking Tijuana residents and Baja officials on hikes.
“People are surprised to discover such wonders exist in Tijuana, and I aim to expose more people to this beauty because it’s essential,” Fernandez said. “We must not let human-made barriers hinder us.”
As border security tightens due to increasing global displacements caused by natural disasters, violence, and wars, more migrants find themselves in areas like the area near Jacumé. This small community of about 100 families includes Kumeyaay tribe members and lies across from a sparsely populated desert near the California town of Jacumba Hot Springs, with a population of about 1,000.
This area has become a temporary home for thousands of asylum seekers waiting to cross under cover of night, only to camp again on the U.S. side after surrendering to U.S. Border Patrol agents.
Fernandez assisted Bioblitz volunteers on the Mexican side near an old crossing station from the 1920s.
“I never imagined so much biodiversity could exist at the border,” said Jocelyn Reyes, a student of Fernandez at La Universidad Autónoma de Baja California, who paused frequently to examine and photograph plants. “It’s fascinating and highlights how much there is to preserve.”
