Humans aren’t the only creatures to make nostalgic returns home

Each fall, universities and schools across the U.S. celebrate homecoming, welcoming alums back to campus to reconnect with old friends and places held dear. But humans aren’t the only ones with a propensity to return to familiar places.

Corinne Richards-Zawacki, professor of biology in the Kenneth P. Dietrich School of Arts and Sciences and director of the Pymatuning Laboratory of Ecology, studies natal philopatric amphibians, that is, amphibians that habitually return to the place where they were born to reproduce.

“One of the unique habitat characteristics that support philopatric amphibians is the area’s abundance of ephemeral ponds, pools that form and dry up yearly,” said Richards-Zawacki.

Ephemeral ponds are shallow and fill up when the water table rises. How much rain falls determines how long it lasts, whereas a deeper pond holds water all year. The ponds Richards-Zawacki studies at the Pymatuning Laboratory of Ecology are about the size of a Cathedral of Learning classroom, but as they dry out, they shrink to the size of puddles or disappear completely.

Many philopatric species are only seen when they return to natal ponds in the spring and spend most of the year living under logs or burrowed in the ground, she said.

While breeding in a disappearing body of water may seem risky, philopatric amphibians find them appealing for a reason — ephemeral ponds can’t sustain some predators, including tadpole-snacking fish.

Make friends with amphibians

The Richards-Zawacki lab studies the evolutionary impact of climate change on wildlife diseases like the chytridiomycosis panzootic, an infectious fungal disease that has contributed to the massive worldwide decline, and even extinction, of amphibian species.

Richards-Zawacki highlighted a few ways people without scientific backgrounds can also contribute to the conservation of philopatric amphibians.

“Many philopatric animals have a high mortality on roads built between where they hibernate and the location of their ponds,” she said. “If there’s a known migration path, people can build underpasses or other safe ways to get across or assist animals with movement across roads on nights where mass migrations are happening.”

Click the photo icons below to meet some philopatric amphibians that make homecomings each year in Western Pennsylvania.