On a gray winter morning, Anjana Parandhaman led a group of researchers and biologists to a makeshift fence next to a Brussels sprout farm near Elkhorn Slough, in North Monterey County. The barricade was constructed from black tarps zip-tied to vertical wooden planks. At the base of the fence, three buckets were sunk into the ground. One of the world’s most endangered species rested inside them. first letter is a drop cap.

“This is so cool,” Parandhaman said, her excitement bubbling into laughter. She plunged her arm into the bottom of one bucket and grasped a wriggling treasure: the Santa Cruz long-toed salamander. The slimy creature crawled across her palms. Parandhaman, an ecology and evolutionary biology researcher at the University of California, Santa Cruz, identified it easily, recognizing the amphibian’s iconic yellow polka dots and spindly toes. For the past year, Parandhaman has led a four-year effort to try to prevent this endangered species from going extinct.

Salamanders, in general, are considered the most vulnerable species in the world, with more than 40% of salamanders species in North America at risk of going extinct. The Santa Cruz long-toed salamander has been endangered for more than five decades, and climate change, agriculture and housing development may bring a swift end to its grip on survival. Conservationists say that some homeowners and farmers who live and work in salamander habitat are ignoring state and federal land-use restrictions by developing land where salamanders breed. The habitat loss is hurting the salamander’s ability to survive as a species.

Santa Cruz long-toed salamanders are only found in a fifteen-mile stretch of land sandwiched between southern Santa Cruz and northern Monterey counties, inhabiting one of the smallest known habitat ranges of any land animal considered endangered by the U.S. federal government. This unique species is an important warning system for ecologists monitoring wetland health. Because the salamanders are especially vulnerable to harmful changes and pollutants in the environment, their extinction would signal to researchers that the entire ecosystem is in trouble.

“It became obvious that if there weren’t proactive things being done, that these populations would start to blink out,”

In an effort to bring the species back from the brink of extinction, Parandhaman and her colleagues at UC Santa Cruz are trying to revive the salamander’s rapidly declining population with a captive breeding program. The project aims to release captive-bred salamanders that are genetically suited for the changing environment into the wild.

“It became obvious that if there weren’t proactive things being done, that these populations would start to blink out,” said Eric Palkovacs, ecologist and professor at UC Santa Cruz leading the captive breeding program.

A homecoming journey

The Santa Cruz long-toed salamander is named for its exceptionally long toes, about the length of long rice grains, and isolated habitat range. It spends the majority of its life underground in coastal oak woodlands. Sprawling oaks and shrubby grasslands create ideal habitat for hiding the salamander’s burrows.

People rarely see these salamanders because of their mostly subterranean existence. But in late fall to winter, between November and February, the salamanders emerge from below ground to breed.

The small creatures travel at night to avoid predators, as they journeys from their woodland homes to the same ponds they were born in two years prior. The five-inch-long critters traverse more than 600 feet on average to complete their homecoming journeys. Their breeding ponds are often found in wetlands and are only filled with water during the winter season.

The males arrive first, spreading out in the pond’s shallow waters as they anticipate the females’ arrival. After they mate, the females lay about 300 eggs in the sediment or attached to reeds. The hatchlings emerge three to four weeks later and begin a three-month transformation from a tadpole-like larva into terrestrial salamanders. The youngsters leave the pond once it starts to dry in the early summer months.

For the past five decades, the salamander’s elegant and predictable life cycle has faced a barrage of threats, as climate change alters seasonal ponds and human development blocks their historical migration paths.

Holding on to survival

In 1933, California’s State Highway 1 opened in Santa Cruz, running through large portions of the Santa Cruz long-toed salamander’s habitat.

Twenty years later, the first Santa Cruz long-toed salamander was discovered in Valencia Lagoon, a wetland on the county’s southern border. Over several decades, the continued expansion of major roads and rapid urbanization began to turn the salamander’s already harrowing nighttime journey into an inevitable flirtation with death.

In south Santa Cruz County, the salamander’s upland habitat in an area called Rio Del Mar became an attractive area for residents to build homes. Beautiful oak trees and expansive grasslands surrounded the properties. Homes were constructed. The fences and curbs that came with them barred the south Santa Cruz salamanders from reaching their breeding grounds.

Just 15 miles south, the Monterey salamander population was grappling with the expansion of farmland near pond sites. Instead of finding oak trees and sagebrush, salamanders crawled through crop fields that don’t provide the same the cover or moisture they need, exposing them to predators, pollution, and dehydration. These groups’ breeding ponds are closer to the ocean and are also threatened by sea level rise.

By 1967, biologists in the U.S. Fish and Wildlife Service noticed the Santa Cruz long-toed salamanders’ numbers were plummeting. That year, the Santa Cruz long-toed Salamander became one of the first animals to be listed under the federal Endangered Species Act. The historic listing led the species to be legally protected, allowing the USFW to enforce regulations to prevent the salamanders from being harmed further.

Reversing the vortex

Ever since, the Santa Cruz long-toed salamander has been classified as a fully protected species by both the U.S. Fish and Wildlife Service and the California Department of Fish and Wildlife. This means that by law, both agencies must prevent any type of harm the salamanders might encounter. In most cases, these agencies protect the salamanders’ habitat, ensuring outside forces are not killing the existing populations. But there is very little they can do to boost the populations’ numbers, Palkovacs said.

This troubled Chad Mitcham, a federal biologist who was put in charge of protecting the Santa Cruz long-toed salamander species more than 15 years ago. The position required him to closely monitor and enhance the habitat of both the southern Santa Cruz and northern Monterey salamander populations. After spending years studying the species, he noticed a troubling pattern: traditional conservation practices were inching the amphibians toward extinction.

Five years ago, Mitcham sounded the alarm about what he had seen — what biologists call an “extinction vortex.” This meant that habitat loss and climate change were shrinking salamander population sizes, resulting in more and more inbreeding. Each generation became less genetically diverse and less able to adjust to their changing environment, causing the population to decline further and further, year after year.

“It got to the point where Chad was pretty convinced that something had to happen or these populations were basically going to disappear,” Palkovacs said. “This downward spiral of smaller populations and less genetic variation was going to continue unless we did something different.”

As Mitcham observed the Monterey population of salamanders dwindling, he also noticed that it was becoming genetically distinct from the Santa Cruz population, which was not disappearing as quickly. He suspected the discrepancy in the two populations’ numbers suggested that the Santa Cruz group was better suited to adapt to harsh environments.

The epiphany led Mitcham to hatch a plan: he wanted to introduce genes from the Santa Cruz cohort into the Monterey populations. In 2019, he brought together geneticists, biologists, conservation nonprofits and government agencies for a meeting that would try to redirect the course of the Santa Cruz long-toed salamanders’ downward trajectory. UC Santa Cruz researcher Barry Sinervo, a prolific lizard researcher who has since passed away, sat among them. His lab leaped at the chance to spearhead a captive breeding project with Mitcham’s federal agency.

In 2021, Santa Cruz long-toed salamanders were captured and brought into Sinervo’s lab for the first time. Palkovacs took over the project in 2022, appointing Parandhaman at the helm of the now well-established captive breeding program. “We’re trying to basically turn around the extinction vortex,” Palkovacs said.

Hatching hope

After collecting wild salamanders from their sunken buckets, Parandhaman and her team packed them gently away into new portable buckets lined with leaf litter. The specimens were driven straight to UC Santa Cruz’s Coastal Science Campus, where they were separated by sex and stored in terrariums inside a greenhouse.

The greenhouse sheltered captured salamanders from both the Santa Cruz and Monterey populations. Hoping to increase genetic diversity in the struggling Monterey division, Parandhaman planned to cross the two populations in artificial breeding ponds.

She had built 30 of these artificial breeding ponds in raised curricular tubs that are staggered in a grid-like pattern on an open dirt lot. The 400 gallon tanks were filled with water, and muck and reeds transplanted from the salamander’s wild habitat. The pools would soon host the captured salamanders so they could breed.

In early January of 2025, Parandhaman placed several males in the artificial breeding ponds and introduced a single female to the mix. The ladies were choosy. They evaluated several options before finally deciding to pick up a sperm packet from a desirable male. Eventually, the females laid their eggs, decorating the ponds’ vegetation like plump grapes.

A few weeks later, small brown “C” shapes resembling a salamander were curled up inside the orb-shaped eggs. Embryos were beginning to develop. Parandhaman and her undergraduate research team monitored the eggs’ development. Team member James Bledsoe eagerly scoured the tanks for larva, leaning his torso over the pond edge and thrusting his face centimeters over the water.

“I had a premonition that they hatched last night,” he said as his hair dunked into water. “I’m not even kidding. I had a dream.”

Parandhaman and her team counted the eggs and moved on to the next pond. In the wild, only 1% of the 300 or so eggs in each clutch will survive past the larva stage due to predation. But hope rides on these protected captive-bred offspring.

A turning point

Since 2021, the captive breeding program at UC Santa Cruz has released around 3,500 captive-bred juvenile salamanders into the wild. This year could mark a turning point in the project: it might be the first time that Parandhaman captures wild salamanders that were originally hatched in the lab.

“What we caught this year could be adults that started their life in our captive breeding facility,” Palkovacs said.

A few years ago, Parandhaman released a cohort of young salamanders into a new pond that showed no previous signs of being inhabited by other wild Santa Cruz long-toed salamanders. Because salamanders imprint on the ponds where they are born in (or in this case released in), Parandhaman is optimistic that the adults she recently captured there are likely from the group that originated in the captive breeding program.

To confirm her suspicions, Parandhaman is developing a DNA identification method to determine whether the salamanders she captures in the wild are from the captive breeding program. To accomplish this goal, Parandhaman cuts a small part off of each salamander’s tail. She then sends the tail sample to the National Oceanic and Atmospheric Administration, which uses genetic analysis techniques to read the DNA within each clipping.  As of March 2025, Parandhaman said the program has enough funding to last until at least August to continue this work, but the future may contain uncertainties.

They will identify unique chunks of DNA, called genetic markers, that are common across captive bred salamanders. If she identifies these unique markers in future wild-caught salamanders, she’ll know that they started life in captivity.

Parandhaman is still in early stages of this process, but she hopes the genetic marking system could help cement the captive breeding programs as a part of the salamander’s recovery plan in the future.

New insights into an ancient species

While the creatures’ origin dates back more than 10,000 years ago to the most recent glacial period, little is known about the Santa Cruz long-toed salamander’s behavior. Because they are nearly impossible to observe in the wild, Mitcham and the UC Santa Cruz team had an unique opportunity to study the amphibian in captivity.

During the program’s first year, Mitcham discovered that the salamanders only breed in the rain, to ensure that their eggs are covered in water once they are laid. They also found out that the Santa Cruz long-toed salamander is cannibalistic, after watching larvae prey upon each other in the tanks. These novel insights are important for understanding salamander ecology as a whole, Mictham says.

An uphill battle

While the team has made significant progress, they still worry that their captive-bred Santa Cruz long-toed salamanders may not survive in the wild. Terris Kasteen, a state biologist who manages the Santa Cruz County salamander populations, says that some homeowners in salamander protected areas pose a threat to the salamander’s ability to breed in the future.

Under the federal Endangered Species Act, homeowners are not allowed to build anything on their properties that might cause harm to the salamanders. The law forbids construction of any structures that might block a salamander’s path and the removal of brush that might protect a salamander’s burrow from predators.

“They’ll start doing it illegally,” said Kasteen. “This is what we don’t want. They could be killing salamanders while they do it.”

But Kasteen says many homeowners she interacts with feel that changing their lives for this tiny creature is an unfair burden. For example, despite its impact on salamander habitat, some residents feel that removing brush from their properties is necessary for fire safety, Kasteen says.

“They’ll start doing it illegally,” said Kasteen. “This is what we don’t want. They could be killing salamanders while they do it.”

Uncooperative farmers are also hindering the research process. In 2023, Parandhaman lost access to a pond located near the McCluskey Slough — a site where she regularly captured and released breeding adults. The farmers on the site were wary of the government’s presence on their farms, and refused to give the researchers permission to conduct surveys on their properties.

When one pond closes, another one opens

In June, Parandhaman will return to the lean-to fence along the Brussels sprout fields. In a bucket, she’ll carry one of the rarest animals in Santa Cruz and Monterey counties. It will be set free in one of the 23 ponds they have left.

She can’t guarantee that they will make it past the fences, or traverse safely through the crops. But she watches their strong tails flick deeper into the water, she’ll hope she’s done enough to see them again.

© 2025 Carly Kay / UC Santa Cruz Science Communication Program