Off-campus UMass Amherst users: To download campus access theses, please use the following link to log into our proxy server with your UMass Amherst user name and password.

Non-UMass Amherst users: Please talk to your librarian about requesting this thesis through interlibrary loan.

Theses that have an embargo placed on them will not be available to anyone until the embargo expires.

Document Type

Open Access

Degree Program

Wildlife & Fisheries Conservation

Degree Type

Master of Science (M.S.)

Year Degree Awarded

2011

Month Degree Awarded

February

Keywords

Shrubland habitat, postfledging, shrubland birds, forest birds, invasive plants, frugivory

Abstract

Early-successional habitats have become rare in much of the eastern United States, largely due to landuse change, forest maturation and the disruption of natural disturbance regimes. In addition to providing nesting habitat for shrubland species of high conservation concern, wildlife openings may be an important habitat for mature-forest birds during the postfledging period – a critical phase in the avian lifecycle with the potential for high mortality. The habitat requirements of birds during this time period are poorly understood. In this study I examined the relationship between habitat and landscape characteristics on; 1) the abundance of forest nesting birds in shrubland habitat during the postfledging season, and 2) the reproductive success of shrubland bird species. And lastly, I also examined the relationship between avian body condition and seed dispersal, with a focus on comparing native and invasive species.

I found that the abundance of forest birds was strongly influenced by landscape characteristics, as well as food abundance and structurally complex vegetation. Shrubland birds varied in their response to habitat variables, but overall productivity was positively related to taller vegetation structure, and was negatively related to lower-dense vegetation. Frugivore diets were generalized, yet they selected native fruit more often than invasive fruit, and invasive fruit negatively affected condition. My findings are consistent with the results of previous studies of habitat use among postfledging birds, and suggest that, like for forest birds, habitat requirements for shrubland birds during the postfledging period differ from those during the nesting season. Hopefully these results will encourage other studies of this important, but poorly understood stage of the avian lifecycle.

First Advisor

David I. King

Share

COinS