As thirsty cows encroach on their only known habitat, one tree frog species faces extinction
By Milo Putnam on October 21, 2023
A parched cow hardly seems like an intimidating threat. What sort of damage can one thirsty cow really do? But when you are the size of a ping pong ball, a towering bovine is a pretty massive disturbance. Let alone a whole herd of cattle.
Such is the case for Pithecopus rusticus, a small frog that can easily fit in the palm of your hand and called the Rustic Monkey Tree Frog by some researchers. The tree frog lives in Brazil’s Atlantic Forest biome— one of the most biodiverse regions on the planet. In the southern part of the biome is a high-altitude grassland known as the Campos de Palmas, where water is a precious resource and sought out by wildlife and livestock alike. For amphibians like the Rustic Monkey Tree Frog, this poses a significant challenge, since their life cycles depend on access to a healthy water source.
You’d be hard pressed to find a Rustic Monkey Tree Frog, as this Critically Endangered animal is edging closer to extinction, according to the recently published second global amphibian assessment, led in part by Re:wild. In a country treasured for its rich biodiversity, more and more land in Brazil is being degraded to make way for agriculture. This destruction is driven by the demand for crops to feed livestock and space for cattle to graze.
“The Rustic Monkey Tree Frog’s story is a cautionary tale about human food systems threatening the wildlife and ecosystems that are critical to our health and the health of the planet,” says Jennifer Luedtke Swandby, Re:wild manager of species partnerships and one of the lead authors of a study published in Nature based on the second global amphibian assessment. “As global leaders look to protect 30% of the planet by 2030, they must be willing to decrease the negative effects of the animal agriculture industry in places that are home to significant communities of biodiversity or threatened species, like the Atlantic Forest.”
The industrial animal agriculture system is the largest driver of deforestation around the world, and especially in Brazil. As global demand for beef products increases, countries like Brazil have shifted priorities to facilitate higher production for higher profits. According to a new investigation from the Guardian, over 800 million trees have been cut down in the Amazon rainforest in just the past six years to feed the world’s appetite for Brazilian beef. This level of deforestation is so vast it can even be seen from space.
Brazil’s natural wonders are in a battle with beef, despite dire warnings about the importance of these ecosystems in fighting the climate crisis. Cattle ranching across Brazil has pushed species like the Rustic Monkey Tree Frog even closer to the verge of disappearing forever.
Amphibians are among those animals paying the price as their homes are destroyed. According to the new global amphibian assessment, when considering the world’s threatened amphibians, the most commonly documented threat is habitat loss, affecting 77% of these species. The leading driver is habitat destruction for agriculture. In the case of the Rustic Monkey Tree Frog, this threat has driven the species even closer to extinction.
Rustic Monkey Tree Frogs are found only in one area of Brazil’s Atlantic Forest, restricted to just a single, small high-altitude field. It wasn’t until 2009 that a group of researchers and students from the Federal University of Santa Maria first scientifically identified this species for science. Five years later these tree frogs were formally described as a new species.
“Against all odds, on a cool January night we discovered a small Monkey Green Tree Frog with unique colors,” says Dr. Elaine Lucas, professor at the Federal University of Santa Maria. “This discovery unveiled an isolated high-altitude grassland as this species’ unlikely sanctuary, where it remains the only representative of their entire genus in the south of Brazil.”
Since their original discovery, only a few individuals of this species have ever been recorded and all of them in this one grassland, despite multiple searches for Rustic Monkey Tree Frogs throughout the region. To date, scientists have recorded as few as 40 individuals of this species in Brazil.
“All amphibians, including this species, play critical ecological roles,” Luedtke Swandby says. “For example, they are a source of food for other species and they help us by managing insect populations. But the status of amphibians worldwide presents a message loud and clear: humans need to change our treatment of the planet. Amphibians are indicators of ecosystem health and as we drive them closer to extinction, we also risk losing the balance they bring to ecosystems around the globe that are essential to our own survival.”
This is where the thirsty cows come in. The home of Rustic Monkey Tree Frogs is just one grassy wetland in a privately owned field with wind turbines. This habitat is far from ideal—it’s set near a roadway and is in the middle of a grassland dotted with cattle and invasive species.
“As we conducted our population monitoring, we were confronted with a disheartening sight,” says Dr. Lucas. “In 2018, the Rustic Monkey Tree Frog's habitat had been deeply altered. The vegetation where they used to lay their eggs had been buried and the habitat excavated to create a water trough for cattle.”
The landowner had modified this area of the wetland to such an extent that it was no longer a suitable habitat for these frogs. In response, the remaining individuals moved to another part of the wetland in an attempt to avoid the life-threatening disturbance. The landowner’s cattle unfortunately use the entire wetland as a water source in addition to their newly constructed water tank, trampling the remaining habitat.
“Regrettably, the wetlands, home to remarkable species like these rare and highly threatened frogs, face neglect and inadequate protection, succumbing to human activities that prioritize short-term gains over long-term preservation,” says Dr. Lucas.
Many believe this species will likely go extinct in the wild. Their future depends on the landowner's collaboration in not draining the wetlands to fill water tanks for their cattle, and limiting their use of pesticides in nearby soybean and potato fields. Additionally, as climate change accelerates drought patterns throughout Brazil, the competition for water sources continues to grow. In order to ensure species like this have a fighting chance in this race for water, conservation intervention is needed before it’s too late.
To help secure a future for the few remaining Rustic Monkey Tree Frogs, Brazilian conservationists devised a drastic plan for this species. Cue the helicopter. In 2022 scientists collected three Rustic Monkey Tree Frogs from their degraded wetland home. The goal of this mission was to create a population safe from threats in the wild. By collecting just two males and one female Rustic Monkey Tree Frog, scientists wanted to limit disturbances to the remaining wild population, while still developing the world’s first conservation breeding program for the species.
These individuals have become the first of this species to be cared for outside of the wild. Thus, the arrival of the animals to Parque das Aves, a zoological park in southern Brazil, was a historic milestone for the conservation program, and for the survival of the entire species.
“To safeguard the Rustic Monkey Tree Frogs from extinction, with support from RAN/ICMBio, we established a backup colony at Parque das Aves,” says Dr. Lucas. “The ultimate goal is to supplement the wild population and reintroduce captive-bred individuals to their natural habitat once secure conditions are reestablished in the wild.”
Using vital field data on Rustic Monkey Tree Frogs, staff at Parque das Aves created a habitat to ensure that conditions to care for these special frogs could be perfected. The artificial home need to match the precise temperature, lighting, humidity, water quality and pH levels of the frogs' home in the wild, and have living plants. As the only members of their species in human care, these individuals are under close observation. Caretakers even installed an infrared camera to monitor the frogs throughout the night.
Over 90% of the Atlantic Forest biome has been destroyed or degraded. This vital ecosystem is one of the most biodiverse areas in the world and is the only home for the Rustic Monkey Tree Frog. In Brazil the production of animal-based foods is responsible for a majority of deforestation. Scientists warn that if this level of destruction continues, these ecosystems will no longer be able to sustain themselves, causing disastrous consequences globally.
“Conserving amphibians has never been more important,” says Luis Fernando Marin da Fonte, director of partnerships and communications for the Amphibian Survival Alliance. “The intensifying plight of amphibians mirrors our own struggle, as we try to protect natural resources and combat climate change as we work toward a sustainable future for all life on our shared planet. Having the courage to change our own habits and advocate for effective changes in the way we relate to the environment and sustainable food production is crucial for a lasting future.”
By harnessing the power of plants for our diets, we can reduce demand for meat from livestock, protect ecosystems and species like the Rustic Monkey Tree Frog. Eating more plants is a direct way to help preserve our planet’s biodiversity. It’s the best thing we can do to help protect the wild that’s left and restore the rest.
Milo is Re:wild's communications specialist working with our partners to share their stories in protecting and restoring the wild. With over a decade of natural resource interpretation and environmental education experience he lives to spark connections between people and wildlife. Milo loves to travel with his husband and is passionate about supporting ethical wildlife tourism.