A tiny amphibian that has recently gained global attention is getting a major conservation boost thanks to months of painstaking work happening mostly out of public view.
After a carefully coordinated breeding effort, Brookfield Zoo Chicago has successfully raised and released 12,244 Puerto Rican crested toad tadpoles, marking the Zoo’s largest single breeding cycle for the critically important conservation project. The recent effort adds to nearly 40,000 tadpoles the Zoo has contributed over the past decade to help restore one of the rarest amphibians on Earth.
“Conservation work like this can be incredibly detailed and time-consuming, but that’s what makes these milestones so meaningful,” said Mike Masellis, Brookfield Zoo Chicago’s lead animal care specialist, in a press release. “From carefully coordinating breeding pairs to hand-counting thousands of tadpoles and tracking toads in the field, every step plays an important role in helping restore this species.”
How Brookfield Zoo Raised and Released Endangered Puerto Rican Crested Toad Tadpoles
Saving a species requires three core traits: patience, precision, and perfect timing.
Puerto Rican crested toad tadpoles.
(Image Courtesy of Brookfield Zoo Chicago)
For the Puerto Rican crested toad, breeding efforts must closely follow Puerto Rico’s rainy season, when wetlands temporarily fill and offer the best chance for tadpole survival. Meanwhile, behind the scenes, Zoo staff coordinate breeding pairs to maintain genetic diversity while recreating environmental conditions that encourage natural reproductive behaviors.
Once the tadpoles hatch, the work becomes even more labor-intensive. Staff count, monitor, and prepare thousands of tadpoles for transport to Puerto Rico, where conservation teams release them into managed aquatic habitats. There, conservation teams watch over them as they undergo metamorphosis and eventually disperse into the landscape.
“Our hope is that years from now, some of these tadpoles will return to the breeding ponds as adults and continue establishing future generations in the wild,” said Masellis.
For the animal care team, the efforts often extend beyond the zoo walls. Last fall, Brookfield Zoo Chicago staff traveled directly to Puerto Rico to help monitor reintroduced toads in the wild. Working with conservation partners, they studied predator threats, habitat quality, and environmental conditions to better understand what helps — or hinders — the species’ survival.
Read More: These Invasive Frogs Were Once Used as Pregnancy Tests — Now They're Carrying a Deadly Fungus
Why the Puerto Rican Crested Toad Is Endangered
Once thought extinct in the wild, the species now survives through ongoing recovery efforts, but it remains endangered. Habitat destruction has dramatically reduced suitable breeding areas, while invasive species continue to threaten eggs and young toads. Climate-related challenges are also adding new pressures, such as rising sea levels and saltwater intrusion disrupt delicate wetland ecosystems.
Puerto Rican Crested Toad
(Image Courtesy of the Brookfield Zoo Chicago)
Today, the last naturally occurring population survives in the Guánica Commonwealth Forest in southwestern Puerto Rico, making conservation efforts especially urgent.
Because amphibians are highly sensitive to environmental changes, scientists often view species like the Puerto Rican crested toad as indicators of ecosystem health. Protecting them can also help preserve the broader habitats countless other species depend on.
How Bad Bunny Helped Make a Rare Toad Famous
In a recent unexpected turn of events, the Puerto Rican crested toad has also become something of a cultural icon.
Millions of people around the world recently got their first glimpse of Puerto Rico’s only native toad thanks to Puerto Rican superstar Bad Bunny, who featured the animal visually in his Grammy Award-winning album DeBí Tirar Más Fotos.
Brookfield Zoo Chicago has also begun letting guests see the celebrity species in person. Earlier this year, two Puerto Rican crested toads went on public habitat display at the Zoo, offering visitors a rare chance to connect with an animal that is usually kept behind closed doors for conservation work.
Read More: Species Slip Through the Cracks of the U.S. Frog Trade, Some Sold at a Premium
Article Sources
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- This article references information from Brookfield Zoo Chicago: Brookfield Zoo Chicago reaches historic milestone for Puerto Rican crested toad conservation efforts with more than 12,000 tadpoles
