At the tail end of winter, as temperatures creep upward, frogs and salamanders make their yearly trip from terrestrial habitats (forests and meadows) back to aquatic habitats (ponds, wetlands, and streams). After toughing out cold winters by hibernating in the ground or nestling into cozy cracks in logs, the critters find their way back to wet habitats to reproduce.
Frogs, toads, salamanders, and newts are amphibians.
Amphibians live on both land and in water. In fact, the word amphibian comes from the root words “amphi,” meaning both and “bios” meaning life. Typically, amphibians hatch from eggs laid in or near water and they begin life as aquatic larvae. The larvae then go through metamorphosis, with their physical features changing to help them become land-dwelling creatures.
Amphibians help us understand ecosystem health.
Amphibians are “indicator” species. They are sensitive to changes in the environment, so their presence or absence in a habitat can provide clues about ecosystem health. Keeping an eye on amphibian populations can reveal information about water quality, plant health, and changes in climate.
What makes amphibians so sensitive to environmental change?
- They are ectotherms. Their body temperature is directly regulated by their environment. If the water temperature in their habitat changes, it can affect their activity and health.
- They breathe through their skin. Amphibians breathe with either gills or lungs (depending on their life stage), but they also take in oxygen through the pores in their skin! Pollutants in the water can pass through their skin and cause health problems.
- They have complex growth processes. Metamorphosis is triggered by a combination of biological and environmental factors. If conditions become unsuitable, an amphibian’s physical development can be harmed.
Amphibian populations are declining worldwide.
Pollution, habitat loss, climate change, and invasive species are causing harm to amphibian species around the world. Amphibians are both predators and prey, so any decline in their populations can have dramatic impacts on the rest of the food web.
We can support amphibians by:
- Protecting their existing habitat. Amphibians need both land and water, plus safe ways to travel between both habitats.
- Preventing water pollution. Amphibians need clean aquatic habitats to reproduce and grow. Chemicals, trash, and excessive amounts of sediment pollute waterways.
- Watching for invasive species. Non-native species, like the American bullfrog (Lithobates catesbeianus), can hurt amphibian populations by eating too many of them or outcompeting them for limited resources. Invasive plants can also reduce amphibian’s access to food and shelter. Browse our Weed & Pest Directory to learn how to identify and report invasive species.
- Participating in amphibian monitoring programs. Each winter, local organizations provide opportunities for volunteers to put on waders and help search for frog and salamander eggs! Get in touch with the Wetlands Conservancy or Metro to find out how you can join.
Our habitat conservation projects help protect amphibians.
Tualatin SWCD works closely with Washington County residents to improve streams, wetlands, and forests. Planting trees and shrubs along streambanks helps keep water cool and protects amphibians from predators. Leaves and branches from these plants deliver food and shelter when they fall into the water. Protecting forest habitats ensures that these animals have safe places to live in the winter.
We keep an eye out for amphibians while visiting project sites. The best way to determine if frogs and salamanders are present is by looking for their eggs. Clumps of eggs create masses in ponds and wetlands during breeding season, typically from late winter to early summer. Tracking their presence from year to year helps us understand changes in the ecosystem.
Want to learn more about the frogs and salamanders living in Oregon?
There are twelve native species of frogs and toads in Oregon. We tend to look for the Northern red-legged frog and Pacific treefrog, as well as the Northwestern salamander and long-toed salamander, and the rough-skinned newt.