OGDEN, Utah (AP) — Biologists in Utah are working to save native boreal toads from extinction in the face of habitat destruction by humans and competition from invasive species like bullfrogs.

The Standard-Examiner reports (http://bit.ly/2w9ECNj ) boreal toads are tough to track. They blend in well with their environment, they’re mostly active at night and they’re not vocal. The only sound they make is a little squeak males use to keep other males away.

That makes it hard for biologists to pin down how many toads live in Utah — but their yearly surveys indicate populations have decreased.

Part of the problem causing amphibian declines, including boreal toads, is a fungus-caused disease — chytridiomycosis, or “chytrid.” It thickens amphibians’ skin so they can’t absorb water or nutrients.

The toads’ biggest plight, however, is people.