Late Attempts Research Articles

Nesting Ecology and Microhabitat of the Eastern Phoebe in the Central Appalachians

-In 1984, a study of the eastern phoebe (Sayornis phoebe) was conducted on the Appalachian Plateau in western Maryland, principally in the Savage River State Forest. Fledging success and mortality patterns were used as indicators of differences in quality of nest-site microhabitats. A total of 229 fledglings resulted from 84 nesting attempts, an average of 2.73 fledglings per attempt. Fledging success was 61.4%, with early nests generally more successful than late nests. Fledging success was similar among nesting structures, with adherent nests having higher success than statant nests, except on rock outcrops. However, late-adherent nests on rock outcrops did have higher fledging success than late-statant nests. The success of new-active and old-active nests was the same. Losses attributed to predators amounted to 70.1% of all losses. Losses attributed to small predators (55.6%) were significantly higher than that from large predators (14.6%). Other losses were attributed to nests falling (13.9%), human disturbance (5.6%), hatching failure (4.2%), adult death/desertion (3.5%) and inclement weather (2.8%). Losses ascribed to small predators increased from early to late nesting attempts on all nesting structures, but less so for adherent nests on rock outcrops. The principal nest predator was probably the eastern chipmunk (Tamias striatus). Stepwise discriminant function analysis was used to distinguish between microhabitats of high-success (>60%) and low-success (?60%) phoebe nests. Evergreen canopy cover (%), height to nest rim and distance to nearest understory tree were greater at high-success nests; while angle of recess in which the nest was built was smaller. Microhabitat variables with no differences among nesting structures, and therefore probably important in overall nestsite selection, included height of rock outcrop or other structure at the nest location, height to nest rim, width of shelf used for support of nest, length of overhanging structure above nest, height to underhanging structure below nest, height of understory trees and percent evergreen canopy cover. Variables associated with access to the nest tended to affect success more than others.

A System of Air Torpedoes: With Remarks upon the Late Attempts at Air Navigation for War Purposes

A System of Air Torpedoes: With Remarks upon the Late Attempts at Air Navigation for War Purposes