Clearcut with seed trees in red pine forests associated with increased occupancy by Eastern Whip-poor-wills

Abstract

Forest management is often used to increase and maintain early-successional forest habitat for breeding birds by emulating natural disturbance with harvesting. However, quantified habitat-use relationships are often lacking, which makes forest management planning challenging for some species. One such species is the Eastern Whip-poor-will (Antrostomus vociferus), a crepuscular, insectivorous, neotropical, migrant bird, designated as a species at risk throughout most of its breeding range. Thus, we determined occupancy of Eastern Whip-poor-wills at 37 sampling points in red pine (Pinus resinosa)-dominated stands harvested using clearcut with seed trees and in white pine (P. strobus)-dominated stands harvested using uniform shelterwood in June 2013 in eastern Algonquin Provincial Park, Ontario. In red pine stands, we found that model-predicted site occupancy increased by 3.3 times from 0.23 where young (<16 years since harvest) clearcuts were absent to 0.76 where young clearcuts were present. Shelterwood harvesting in white pine stands, by contrast, was unassociated with occupancy. Our data suggest that an aggregated mean total of 12 ha of clearcuts per 100 ha (interquartile range: 1.5–18 ha) of mature pine-dominated forest is associated with significantly higher occupancy by breeding Eastern Whip-poor-wills, and that the clearcuts can be composed of various sizes (interquartile range: 3–42 ha) and ages (interquartile range: 5–24 years since harvest). Given that similar relationships have been found by others elsewhere, clearcuts may increase the occupancy and abundance of breeding Eastern Whip-poor-wills in other regions and forest types throughout northeastern North America.

Keywords: Aerial forager - Forest management planning - Goatsucker - Logging - Nightjar - Silviculture