Scott Connelly was perplexed to see a dramatic decline of frogs at his research site in Panama.

During a period of a few years, an array of frog species seemed to vanish into thin air, despite being in one of the most biologically diverse places on Earth.

Connelly, a doctoral student at the Odum School of Ecology, led a groundbreaking study in Panama analyzing the effects of the chytrid fungus – a virulent fungus that decimates amphibian populations at an alarming rate – on frog species and surrounding ecosystems.

The study closely examined how the absence of frogs, specifically tadpoles, disrupts the ecological balance in stream environments.

Tadpoles play an important role in stirring up sediment, recycling nutrients and grazing on algae. Without them, streams turn into algal dead zones, blocking sunlight which can hinder photosynthesis and decrease nutrient-rich food for other organisms.

The chytrid fungus breaks down the keratin in frogs’ skin, making it slowly slide off. Since tadpoles only have keratin in their mouths, the fungus doesn’t kill them until they develop.

Connelly and colleagues suspect that chytrid’s toxins or the frogs’ inability to osmoregulate are possible causes of death.

Regardless, all frog populations are declining in frightening numbers.

“It’s an eye-opening but unfortunate way to study animals,” Connelly said. “It’s hard to document an extinction, but we are excited to have done before-and-after studies.”

With this data, researchers are better able to pinpoint how the fungus spreads and how to avoid catastrophic consequences.

Catherine Pringle, a research professor in the Odum School of Ecology, and Karen Lips of Southern Illinois University, introduced the study to the National Science Foundation.

Pringle emphasized the large-scale importance of finding a solution to prevent undesirable effects.

“Frogs eat many pest species, including mosquito larvae that spread numerous human diseases,” she said. “They protect humans by keeping insect populations in check.”

Tom Barnum, also a doctoral student, will study the increased amount of aquatic insects in the area and how they replaced tadpoles’ role as algal grazers.

Researchers including Connelly will focus on rehabilitating infected frogs. Many are collected and brought to zoos and gardens to receive anti-fungal treatments.

The Atlanta Botanical Garden and Zoo Atlanta house infected frogs and support breeding programs to re-introduce treated individuals back into the wild.

Scientists try to educate locals by discouraging contact or relocation of the frogs. The frog species Atelopus zeteki, one of the national symbols of biodiversity in Panama, is now possibly extinct, Connelly said.

“What’s happening is not natural. These frogs are disappearing faster than extinctions in the past,” he said. “This is a wake-up call for people to see that the world is changing from human-driven activities.”