Abstract

Surrounding land use influences avian community structure; moreover, anthropogenic manipulation of habitat can alter bird species richness and composition. In the first chapter of my thesis work, I conducted avian surveys at 20 sub-boreal peatlands in eastern Minnesota and western Wisconsin to detect correlations between land development and bird community structure. Peatlands are wetlands that accumulate decaying organic plant material (peat) and provide valuable and diverse habitats to a variety of flora and fauna. I measured urban and cropland development at three spatial scales (500 m, 1000 m, and 2500 m radii). Effects of development on avian communities also were assessed with respect to distance from a major metropolis using three zones: counties inside the city (metro), counties immediately adjacent (collar), and rural counties adjacent to the collar (fringe). I predicted that the zone with intermediate levels of disturbance would have greater species richness (intermediate disturbance hypothesis) and that there would be a correlation between differences in community species composition (i.e., species turnover) and increased levels of development. Urban development influenced avian communities more than agricultural development and avian communities were different among the zones in species composition and partly in species richness. Statistical analysis identified negative relationships between urban cover and the proportion of human intolerant species at all three spatial scales. In the second chapter of my thesis work, I created a rapid-assessment model of habitat quality designed to detect relationships of landscape variables such as peatland area, degree of isolation from other wetlands, extent of adjacent economic development, and vegetative structure on bird community composition. I used rapid-assessment model, known as a hydrogeomorphic model (HGM), that numerically combines landscape features to predict the value of habitat to bird species diversity (functional capacity) Following HGM procedures, I predicted functional capacities at 20 sub-boreal peatlands When compared to observed species diversity, however, no relationship was found with predicted diversity levels. Of the model variables only vegetation structure was related to bird diversity. I suggest that a new model needs to be developed in order to assess the value of peatlands to support peatland bird communities.

Advisor

John D. Krenz

First Committee Member

Marrett D. Grund

Second Committee Member

Bradley J. Cook

Date of Degree

2012

Language

english

Document Type

Thesis

Degree

Master of Science (MS)

Department

Biological Sciences

College

Science, Engineering and Technology

Creative Commons License

Creative Commons Attribution-Noncommercial 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.