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Fish & Aquatic Life: Sensitive Amphibians

Relationship between forest age, water temperature and abundance of tailed-frogs 
 
Source: H. Welsh, U.S.F.S. - PSW, Redwood Sciences Lab, Arcata, CA

Tailed frogs are most abundant in old growth forests, where water temperatures remain cool.  Note that few frogs were found in forests less than 100 years old, or in forests older than 100 years where water temperatures rise above 15 degrees C. Tailed frog eggs cannot survive temperatures in excess of 18.5 degrees, and this temperature may be attained if forest canopy is removed through logging. Data are from  H. Welsh, U.S.F.S. - PSW, Redwood Sciences Lab, Arcata, CA. 

Graphs and photographs from Dr. H. H. Welsh, Redwood Sciences Lab

From the Mattole River Basin:    

Richness of amphibian species in 3 forest cover types (47 KB)

Air temperatures vs. distance from stream for three forest types (45 KB)

Abundance of Black Salamanders in perennial and intermittent streams (40 KB)

From regional studies:

Number of tailed frogs plotted against age of forest and air temperature (45 KB)

Abundance of So. torrent Salamander vs. % canopy (35 KB)