Reconstructing Velocities of Migrating Birds from Weather Radar — A Case Study in Computational Sustainability

Abstract

ArticlesSUMMER 2014 31 E cological processes that occur at global scales are among the most impressive natural phenomena on Earth; they link environments across the globe and capture the imagination of observers. For example, billions of North American birds, representing more than 400 species, migrate annually, often thousands of miles, frequently under the cover of darkness, between breeding and nonbreeding areas. There is an urgent need to understand global processes in order to mitigate threats from anthropogenic change. For example, human-made collision hazards are killing hundreds of millions of birds annually (Crawford and Engstrom 2001;Longcore, Rich, and Gauthreaux 2008), and direct and indirect habitat alteration is reducing stopover habitats vital for birds to refuel during migration (Bonter, Donovan, and Brooks 2009;Veltri and Klem 2005). Our ability to mitigate this anthropogenic mortality relies on a detailed understanding of the magnitude and composition of migration in time and space so we can take actions such as protecting critical stopover sites and turning off wind-turbines and lights on man-made structures at key places and times during migration.However, because of their scale and complexity, global phenomena are also very difficult to study. Bird migration is

Bird mortality during nocturnal migration over Lake Michigan: a case study

“…We used a Matlab program written by Dan Sheldon of the University of Massachusetts Amherst and NASA's Radar Software Library to de-alias the velocity data (Farnsworth et al 2014). We then used custom R code to produce a velocity azimuth display (VAD) profile from each range annulus of each 0.58 sweep (sensu Browning and Wexler 1968).…”

Towards the Automatic Classification of Avian Flight Calls for Bioacoustic Monitoring

“…These sources include weather surveillance radar, which provides insight into the density, direction, and speed of bird movements but little to no information about the species actually migrating [9], tracking devices that provide information about the location and activity of individuals but little information about population behaviors, marking (e.g. banding, ringing, or color marking) and later recapturing individuals, with similar constraints, stable isotope tracking of the changes in key elements to define movements of birds [10, 11], and crowdsourced human observations, made almost exclusively during daytime hours and of limited use for studying nocturnal migratory flights other than by proxy [12].…”

Morning flight behavior of nocturnally migrating birds along the western basin of Lake Erie

“…, Farnsworth et al. , Sheldon ). The VAD profile gives an average ground speed and track direction of flight for migrants at different altitudinal bands around the radar station.…”

“…For migrating birds, velocity values can approximate the general, broadfront direction they are moving. We used a Matlab program written by Daniel Sheldon at The University of Massachusetts Amherst to analyze radar profiles to produce velocity azimuth display (VAD) profiles (Sheldon et al 2013, Farnsworth et al 2014, Sheldon 2015. The VAD profile gives an average ground speed and track direction of flight for migrants at different altitudinal bands around the radar station.…”