Habitat Development Field Investigations, Miller Sands Marsh and Upland Habitat Development Site, Columbia River, Oregon. Appendix C. Inventory and Assessment of Prepropagation Terrestrial Resources on Dredged Material

摘要

A study of existing conditions of terrestrial ecology at Miller Sands Island showed that the vegetation on the main island consists of open grassland areas and wooded areas. That the grassland contains scattered trees and shrubs indicates that succession from open grassland to wooded areas is occurring on the island. Sixty-five different species of birds were observed. Changes in numbers and species are attributed to the emigration of waterfowl and shorebirds. During spring and fall migrations the island and environs provide resting and habitat. While birds have apparently colonized the island, mammals, amphibians, and reptiles have not. No amphibians or reptiles were observed during a search of suitable habitats. Since only a few small mammals were captured, numbers on the island are believed to be limited, with the exception of nutria. Nutria, which have relatively high water mobility, were observed during each sampling period and maintain trails in all habitat on the island. (Author)