Individual study: Amphibian use of Chehalis River floodplain wetlands
Henning J.A. & Schirato G. (2006) Amphibian use of Chehalis River floodplain wetlands. Northwestern Naturalist, 87, 209–214
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
A replicated, site comparison study in 2003–2004 of two restored wetlands in southwestern Washington, USA (Henning & Schirato 2006) found that amphibian species richness was similar and abundance tended to be higher in restored compared to natural wetlands. Abundances were significantly higher at restored and one natural wetland compared to the other three natural wetlands. Restored and natural wetlands had similar species richness (4–5 species). Pacific treefrogs Pseudacris regilla were only found in natural wetlands. Abundances of the other five species varied between wetlands. Significantly higher number of amphibians emigrated from the restored compared to natural oxbow wetlands (29–58 vs 0.01–0.25/trap night). Abundance was highest in wetlands with intermediate hydroperiods (>7 months) compared to those with temporary or permanent water. Two restored (emergent) and four natural (emergent and oxbow) wetlands were surveyed. Restoration in 1997–1998 involved blocking drainage ditches by constructing water control structures and embankments. Amphibians were monitored using fyke nets and one-way traps in January–June 2003–2004.