Does emergent vegetation influence Rana clamitans and Rana pipiens densities around pond perimeters?

Abstract

...In our survey of several ponds in the Cheboygan and Emmet County areas, we noticed that ponds with dense foliage appeared to contain more frogs than those with sparse foliage. Based upon this information, we hypothesized that emergent vegetation limits Rana clamitans and Rana pipiens densities around a pond's perimeter, our null hypothesis being that frog density is independent of percent cover by emergent vegetation.