As human activity alters the natural environment, the environmental suitability for supporting some forms of life is reduced, while its ability to support other forms is enhanced. In Iowa, 90% of the original 4.5 million acres of wetlands have been drained and converted primarily to agricultural use. New wetlands are being rebuilt or former wetlands restored; however, whether or not such efforts are able to duplicate the unique habitats of the original communities remains to be seen. The purpose of this research was to address whether reconstructed wetlands serve as adequate replacements for natural wetlands by supporting similar communities of amphibians based on physical and biotic differences. In early and mid-summer, we used minnow traps to sample 19 wetlands of North-Central Iowa, 9 natural and 10 restored, and measured the pH, depth, and temperature of the trap locations. An assortment of macroinvertebrates and 8 species of vertebrates were collected: the leopard frog, chorus frog, American toad, tiger salamander, fathead minnow, brook stickleback, green sunfish, and the common carp. For the most part, natural and restored wetlands did not significantly differ, but we discovered some relationships between species with each other, pH with wetland type, and species with wetland type. There was a positive association between the presence/absence of Bufo americanus and Pseudacris triseriata. The pH levels of restored wetlands tended to be more alkaline. Pimephales promelas, crayfish, Belostoma, and Anax were positively associated with natural wetlands. This suggests that natural wetlands are more suitable for some species, but not specifically for amphibians.
Jason Kuehner, ’02 Decorah, IA
Major: Biochemistry and Molecular Biology
Sponsor: Dr. S. Andy McCollum