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Sensitive Amphibian Information in KRIS

KRIS Web Background Pages: Sensitive Amphibians

Although extensive data is not available on amphibians of the Noyo River basin. A California Department of Fish and Game memo dated February 10, 2000 documented the existence of tailed frogs in a tributary to the North Fork of the South Fork Noyo River (Macedo, 2000). Kitchen (1992) documented that southern torrent salamanders occurred in Parlin Creek, in the South Fork Noyo basin (see note from Dr. Hartwell Welsh). Data from the Mattole Basin are provided below for insight into known relationships of sensitive amphibians and riparian habitat change related to land use in northwestern California.

Redwood Sciences Lab Findings from the Mattole River

Data below shows findings from Redwood Sciences Lab regarding the relationship of forest canopy conditions and the presence and absence of sensitive amphibians on the Mattole River (Welsh, unpublished data). Water temperatures were also measured associated with each canopy type and relationships are explained below.

Salamander and frog use of 3 forest types 5 KB
Data provided from work in progress at US Forest Service Redwood Science Lab, Arcata

The Chart above shows that tailed frogs and southern torrent salamanders require habitat conditions provided by late seral (LateSeral) or old-growth forests and these species are greatly diminished in second growth forest (SecondGro) habitats. Neither of the species occur in mixed forest/grassland (GrassMix) ecosystems. The black salamander finds optimal habitat in streams of late seral forests but is still found at lower levels in other forest types. Data provided from studies in progress at US Forest Service Redwood Sciences Lab, Arcata.

Amphibian use of 3 forest types 7 KB
Data provided from work in progress at US Forest Service Redwood Science Lab, Arcata

The graph above shows that Pacific giant salamanders are most abundant in late seral forests but still thrive in second growth and even mixed grassland/forest habitats. Yellow-legged frogs actually increase as canopy conditions decrease. Pacific tree frogs were not found in late seral environments and are most abundant in grassland/forest habitats.

Water temperature and salamander survival 8 KB
Data provided from work in progress at US Forest Service Redwood Science Lab, Arcata

The water temperature of this unnamed tributary of the Mattole River reaches levels that are stressful or lethal for southern torrent salamanders (17.2 degrees C). This tributary, which enters the Mattole downstream of Little Finley Creek, had torrent salamanders prior to logging. It represents the mixed second growth/grassland forest type in the Redwood Sciences Lab studies from which these data were derived.

References

Kitchen, D. 1992. Baseline studies of birds, mammals, amphibians, and reptiles and basic WHR analysis of wildlife on the Jackson State Demonstration Forest. Humboldt State University, Arcata CA. Dept. Wildlife & Fisheries. (Unpublished report)

Macedo, R. 2000. Abbreviated Electrofishing Survey and Watercourse Classification of Unnamed Tributary to the North Fork of the South Fork Noyo River; Downstream of the Brandon Gulch / North Fork of the South Fork Noyo River Confluence; Brandon Gulch 2000 THP; Jackson Demonstration State Forest, Mendocino County. Region 3, CDFG, Yountville, CA.

Welsh, H.H. Redwood Sciences Laboratory, Arcata, CA.