Date of Award

12-2004

Level of Access

Campus-Only Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Wildlife Ecology and Wildlife Conservation

Advisor

Malcolm L. Hunter Jr.

Second Committee Member

Raymond J. O'Connor

Third Committee Member

William B. Krohn

Abstract

This study investigates approaches to habitat evaluation for forest songbirds using fledgling observations to document successful nesting. The initial work involved morning and afternoon point and transect surveys to test feasibility of fledgling detection and identification in 4 replicates of 3 forest types in northern New Hampshire. Mean fledgling detection rates were significantly higher for transect than point surveys. We then compared a transect-based behavior-mapping protocol, adapted from traditional spot-mapping, to nest-searching and monitoring on 3 sites and to constant effort mist-netting on one site in western Maine. Compared with nest searching, behavior mapping detected more occupant species (98% vs. 57%), successful species (93% vs. 39%), home ranges (97% vs. 42%), and successful pairs (95% vs. 29%). Compared with mist-netting, behavior mapping detected more occupant species (98% vs. 56%), successful species (100% vs. 38%), home ranges (98% vs. 37%), and successful pairs (100% vs. 28%). Data for species composition, home range abundance, pairing success, and nesting success on 55 15-30 ha sites, ranging from urban neighborhoods to primary forests, provided a basis for developing and testing candidate metrics to assess forest biological integrity. The nine selected metrics include 3 representing species richness and composition, 4 representing nest guild structure, and 2 representing abundance and condition. We used breeding data from a managed Acadian spruce-fir ecosystem to explore relationships among bird home range density, pair density, and nesting success. Relationships among the three metrics were not consistent among species. Behavior-mapping and vegetation data from 11 20-ha sites (28 site-years) in northern New Hampshire and adjacent Maine provided a basis for evaluating effects of partial cutting on breeding birds in Acadian spruce-fir forest. Mean values differed significantly between partially cut (residual basal area 14.3 to 22.4 m2/ha) and control sites (residual basal area 28.5 to 36.2 rn2/ha) for 13 of 48 vegetation variables considered. Eighteen of 24 bird species analyzed showed no significant differences in abundance between partially cut and control sites. Harvested sites supported significantly more home ranges for 5 species and significantly higher nesting success for 2 species.

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