Where Do Acadia’s Amphibians Cross the Road? Mapping Hotspots With Volunteers

From the chirp of a spring peeper to the flash of a bright orange red eft, amphibians are part of what makes the northern forest. At least 11 species live in Acadia National Park, where they play roles in food webs, nutrient cycling and other ecosystem processes.

A red eft, the juvenile land-dwelling stage of the eastern newt. NPS photo / Jack Byrley.

Vital — and vulnerable

Amphibians are declining worldwide, and Acadia’s are no exception. Part of their fragility comes from living two lives, one on land and one in water. Many migrate each season to reach breeding wetlands, and roads that cut across the landscape become deadly crossings. Rural roads are a particular concern — including the network of roads the park itself maintains.

The timing of seasonal road closures is shifting with climate change and visitor numbers, so park managers need a way to see how that affects amphibians.

Surveys on rainy nights

Marisa Monroe, an Acadia Science Fellow and University of Maine graduate student, planned to survey the park’s roads over two field seasons, each running from early spring to late fall. On rainy nights, volunteer surveyors would walk or bike the park roads, recording amphibians both living and dead.

To cover that much ground, Monroe planned a citizen-science program drawing volunteers from local communities, using her background in international environmental education and interpretation to reach people of many backgrounds. Training would be adapted from the Maine Big Night citizen-science initiative.

As park wildlife biologist Bik Wheeler put it, the park does not yet know when or where amphibians cross its roads, especially outside the early-spring rush to lay eggs — and the work would give a much fuller picture of their movements and how to protect them.

What it will produce

• Maps of crossing hotspots, so researchers and managers can assess risk, predict amphibian movements and act to protect them
• a baseline for future amphibian research in Acadia and at other national park sites
• new survey methods and a model for volunteer data collection

The aim: to keep Acadia’s forests and wetlands full of newts, salamanders and frogs, with benefits that ripple through the whole ecosystem.

Sources

Based on "Research Brief: Informing Management of Amphibian Road Crossings in Acadia National Park," National Park Service; a work of the United States government in the public domain.