A New Checklist of Amphibians in 292 National Parks

Woodhouse's toad, Glen Canyon National Recreation Area. Image from the NPS's page.

Why amphibians

Frogs and other amphibians are highly sensitive to environmental change, so whether they are present, absent or abundant says a lot about an ecosystem's health — and much of the news is bad. The International Union for Conservation of Nature describes 35% of North America's amphibian species as vulnerable in at least part of their range, and U.S. amphibian populations are declining by about 4% a year on average.

National parks matter enormously: covering about 3.5% of the country, Park Service lands hold 65% of its amphibian diversity. That makes amphibians a high conservation priority, and a project by the Park Service's Inventory & Monitoring Division makes the work easier.

Western tiger salamander, Teton Range, Wyoming. Image from the NPS's page.

Updating the list

To protect amphibians, managers first need to know which species live in each park. The main source is NPSpecies, the Park Service's online database of species in the parks — but species lists need constant upkeep. Many parks' amphibian lists hadn't caught up with recent sightings or changes in taxonomy. So Inventory & Monitoring scientists and the U.S. Geological Survey, with amphibian experts around the country, combed through old and new park records to update them.

Canyon treefrog, Grand Canyon National Park. Image from the NPS's page.

What's known now

The Park Service now has an up-to-date amphibian checklist for 292 of its 424 units, with current taxonomy, international and state conservation rankings, a supporting reference for each record, and notes.

• 230 amphibian species occur in the parks — 65% of the 354 in the United States.
• Parks in the Southeast and Northeast, where salamanders outnumber frogs and toads, have the most species: the Southeast recorded 40 frogs and toads and 96 salamanders.
• The Blue Ridge Parkway, a 470-mile corridor from Shenandoah to Great Smoky Mountains National Park, has 46 documented species (plus 5 possibly present and 2 nearby), including 5 salamander families and 19 species of Desmognathus alone. Yellowstone, at 3,468 square miles one of the largest in the continental U.S., has just 5.
• Southwestern parks have the largest share of at-risk species, about 25%: near threatened, vulnerable or endangered.

Sierra newt, Yosemite National Park. Image from the NPS's page.

How it's used

An accurate list lets managers judge how common or rare each species is, identify threats such as climate change and invasive species, and weigh the value of protecting more habitat inside or outside park boundaries — the difference between acting for at-risk species and overlooking them. Parks planning wetland work can check which species are there; parks planning eDNA or other surveys can pick their targets; and knowing what lives in a park is the first step in judging its climate vulnerability. The project is also a model for updating lists of other groups.

Columbia spotted frog, Yellowstone National Park. Image from the NPS's page.

More: B.J. LaFrance, A.M. Ray, R.N. Fisher and others, "A Dataset of Amphibian Species in US National Parks," Scientific Data 11:32 (2024).

Sources

Based on "Updated Species Database Will Help Boost Amphibian Conservation Across the National Park Service," Inventory & Monitoring Division, National Park Service; a work of the United States government in the public domain.