A created forested wetland contained similar numbers of mammal and amphibian species and a lower number of bird species than an adjacent natural forested wetland in Maryland, USA.

  • Published source details Perry M.C., Sibrel C.B. & Gough G.A. (1996) Wetlands mitigation: partnership between an electric power company and a federal wildlife refuge. Environmental Management, 20, 933-939


This study is summarised as evidence for the following.

Action Category

Create wetland

Action Link
Amphibian Conservation

Restore or create wetlands

Action Link
Terrestrial Mammal Conservation
  1. Create wetland

    A site comparison study in 1994–1996 of a created forested wetland in a Research Refuge in Maryland, USA (Perry, Sibrel & Gough 1996) found that the created wetland supported a similar number of amphibian species to an adjacent natural forested wetland. Ten species were captured in the created wetland (284 individuals) and 11 in the adjacent natural wetland (87 individuals). Spotted salamander Ambystoma maculatum was only found in the created site and wood frog Rana sylvatica and marbled salamander Ambystoma opacum only in the natural wetland. As mitigation for loss of wetland, a 9 ha wetland was constructed in 1994, of which 5.5 ha was forested wetland. Amphibians were captured in pitfall and flannel traps along drift-fencing within the created and adjacent natural forested wetland. Trapping was conducted several times during the year.


  2. Restore or create wetlands

    A site comparison study in 1994–1995 of two forested wetlands in Maryland, USA (Perry et al. 1996) found that a created forested wetland had the same mammal species richness as a nearby natural site, but different species composition. No statistical analyses were performed. Four mammal species were recorded both on the created site and the natural site. Meadow vole Microtus pennsylvanicus was more abundant at the created site (0.17–0.58 individuals/trap/day) than at the natural site (0 individuals/trap/day). The same pattern was seen for House mouse Mus musculus, and domestic cat Felis catus (no data reported). White-footed mouse Peromyscus leucopus was less abundant at the created site (0–0.17 individuals/trap/night) than at the natural site (0.14–0.67 individuals/trap/night). Pine vole Pitymys pinetorum, gray squirrel Sciurus carolinensis and opossum Didelphis virginiana were found only in the natural site. Forest wetland (5.5 ha) was created on a former firing range. The site was graded in December 1993 and planted with native vegetation in spring and summer 1994. Mammals were live-trapped from November 1994 to March 1995 on the created site and adjacent natural forest wetland, using Sherman traps and larger box traps. Tracks were monitored in sand pits in summer 1995.

Output references

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