The effect of understory vegetation density on the distribution of American Redstarts (Setophaga ruticilla) in a hardwood forest.

Abstract

The American Redstart is a wood warbler that is in population decline in northern Michigan. This study investigates the effect understory vegetation density has on the distribution of American Redstarts in hardwood forests, in order to better understand how deforestation and forest regeneration will affect the population in the future. Transects were established to sample vegetation and to census the local American Redstart population. There is significant positive correlation between understory vegetation density and American Redstart distribution. There is no significant correlation between American Redstart distribution and canopy cover, presence of other bird species, or distance from a lakeshore. This study indicates that American Redstarts choose to inhabit areas of hardwood forests with denser understory.