Novel Methods for Assessing Abundance and Population Dynamics of Three Forest Birds in Managed Young Forests using Autonomous Recording Units

Title: Novel Methods for Assessing Abundance and Population Dynamics of Three Forest Birds in Managed Young Forests using Autonomous Recording Units Abstract: Ruffed grouse (Bonasa umbellus) are highly revered by both hunters and non-hunters across the Commonwealth, but unfortunately, eastern grouse populations have been consistently declining over the past several decades primarily due to young forest habitat loss. The introduction of West Nile virus (WNV) into the United States has only accelerated this decline over the past two decades. In addition to habitat loss and disease, changes in weather, such as wetter springs and warmer winters, could negatively affect grouse production and recruitment, and, thereby, overall abundance. In fact, the 2015-2025 Pennsylvania State Wildlife Action Plan includes ruffed grouse as a Species of Greatest Conservation Need and specifically highlights the need to determine the impact of changing spring weather conditions on grouse production and determine the relative contributions of various factors (e.g., disease, weather) to juvenile mortality. We propose to build on existing work using autonomous recording units (ARUs) to assess patterns of grouse occupancy to further explore how disease, weather, and interactions between these factors affect grouse abundance and metapopulation dynamics (site colonization/extinction rates). Knowledge of which factors drive site colonization and extinction will inform forest managers on how best to implement habitat management efforts while buffering grouse populations from negative weather and disease-related impacts. This project will evaluate the relative effects of various factors on ruffed grouse population dynamics and will develop a robust method for estimating and monitoring changes in grouse abundance, not simply occupancy, throughout the Commonwealth. In addition to ruffed grouse, we also propose to monitor populations of two other forest birds of high conservation interest: the American Woodcock (Scolopax minor) and the eastern whip-poor-will (Antrostomus vociferus).Populations of both of these species are in a state of long-term decline. Like ruffed grouse, it is thought that the management of forested landscapes is likely to benefit both species because they specialize on the younger seral stages of forest succession. The 2015-2025 Pennsylvania State Wildlife Action plan lists the American woodcock as a Species of Greatest Conservation Need and explicitly highlights the following research need for the species: “Investigate impact of changing spring weather conditions on migratory chronology, peak display period, and juvenile production”. This work would clearly address this research need while also providing a novel perspective into the role of habitat in driving the species’ ecology. The 2015-2025 Pennsylvania State Wildlife Action plan also lists the eastern whip-poor-will as a Species of Greatest Conservation Need and explicitly highlights the following two research need for the species: 1. Determine the key features that constitute high quality Whip-poor-will habitat in Pennsylvania and 2. Determine response of this species and others to silvicultural treatments especially for young forest / early succession habitats. As with our woodcock aims, this work would clearly address these research needs while also providing novel perspectives into the role of habitat in driving the species’ ecology and informing conservation.