3 minute read

5 Curious Facts about Fjord Amphibians

1. What's the racket?

Spring and summer nights on the Olympic Peninsula are dominated by the siren calls of the male Pacific Chorus Frog (Pseudacris regilla). Also known as the Pacific Tree Frog, these little guys (they average from 1-2 inches long) pack a big musical punch with calls that can be as loud as 87 decibel levels (most human conversation is 50 dBs and a police siren is typically 100 dBs – and your fancy Apple watch warns you if you exposed to sounds over 80 dBs).

According to the Burke Museum’s Herpetology webpage, varieties of frogs have specially developed eardrums which are connected to the lungs that work to equalize the pressure between the outer and inner surface of the eardrum thereby protecting it from the otherwise deafening mating calls.

2. Don't kiss a frog.

He’s happy with his amphibious life & will not turn into a prince for you. You may also get misery from the encounter. Bacteria are happy existing on frogs and many toads and salamanders release toxins to protect themselves from predators (or eager humans that pick them up).

3. Night lurkers.

Many of these species are crepuscular (most active at dawn and dusk) or nocturnal (active at night), making observation difficult. Although the Northern Rubber Boa (Charina bottae) is the most northerly residing boa, its crepuscular hunting habits make this snake far less known than the Common Garter Snake (Thamnophis sirtalis). This species is found throughout the Pacific Northwest and since it is not very heat tolerant, they love the damp forests of the Olympics lurking under rocks and logs during the day and hunting at night. This species has special cold weather adaptations that allow it to keep their brain at a healthy warm temperature, while the rest of their body can reach temperatures less than 44°F. This boa at 21 to 26 inches is significantly smaller than their cousin the Boa Constrictor of South America (3 to 13 feet), but it also kills prey (mice and voles) by constriction.

4. A BIG Baby.

The Pacific Northwest is home to one of the largest terrestrial salamanders in North America – the Pacific Giant Salamander (Dicamptodon tenebrosus) Up to 13 inches they are typically found in southwestern Washington. Cope’s Giant Salamander (Dicamptodon copei), measuring up to 8 inches, is the giant of the Olympic Peninsula. Favoring cold mountain waters, this salamander often does not ever metamorphize into its terrestrial form preferring to live out its days with feathery gills in a larval form bound to the aquatic realm. Interestingly, the individuals do reach sexual maturity, but physically they resemble the larval stage of other salamanders. Only a few specimens of the physically mature salamander of this species have ever been found. Why these salamanders stay in this child-like-state is still poorly understood.

5. Skin Breathers

If you find an amphibian and want to touch it, please be mindful that frogs and salamanders breathe through their skins and lotions and chemicals on your hands can be harmful to them.

Further Reading

If you would like to know more about the reptiles and amphibians of the Pacific Northwest, there are many helpful guidebooks and websites. Amphibians of the Pacific Northwest (2016) and Amphibians of Oregon, Washington and British Columbia: A Field Identification Guide (2020) both provide a good grounding in the subject.