The effects of forest vegetation composition on avian abundance and diversity

Abstract

We investigated the differences in the bird and plant communities between the AmeriFlux1 tower and FASET2 tower land plots at the University of Michigan Biological Station in Pellston, MI. We compared various relationships between the bird and vegetation communities located on the two plots including tree size, tree species, ground cover, number of birds, and bird species richness. We conducted an avian point count survey on 16 different transects amung the two plots. We also sampled the vegetation at 23 points along various transects by measuring diameter at breast height (DBH) and estimating the percentage of ground cover. We found that there was a significant relationship between the amount of ground cover and the bird species richness and abundance. There was also a marginally significant relationship between the number of trees and the number of birds. We also discovered that the basal area of the surrounding trees had an effect on the number of birds counted, and the species richness. Additionally, we determined that there was a significant difference in species richness between the two tower plots. In conclusion, we found that there were notable variations in the bird communities at different points along the transects within the two plots, as a result of the differences in vegetation structure.