Enabling Aeroecological Studies Through Advancements in Radar Technology

The aerosphere supports a range of animal life both at the Earth’s surface and in the air. While monitoring the movements and activities of terrestrial animals can be demanding, observation of volant organisms are even more challenging because they require novel technologies. Here we focus on the analysis of animal movements using radar. It has long been known that radio waves scattered from flying organisms (bio-scatter) can be detected and processed using radar. Depending on the particular design, radar can be used to track individuals, observe the movements of organisms over large spatial and temporal scales, and to some extent discriminate between and identify different taxa. Indeed, numerous studies of birds, bats, and insects have been assisted through the use of radar systems that continue to advance based on the development of innovative hardware and signal processing capabilities. In this presentation we explore how these evolving technologies can be applied over a range of spatio-temporal scales.  For example, NEXRAD (Next-Generation Radar) operates continuously and provides near complete spatial coverage across the continental U.S.  Data from this network of weather surveillance Doppler radars (WSR-88D), operated by the National Weather Service, are streamed over the Internet to a central processing facility and made available in near real time. Although designed to collect meteorological data, the WSR-88D also regularly detect bio-scatter. Together with complementary weather observations, NEXRAD data provide unprecedented opportunities to observe birds, bats, and insects in the aerosphere on both local and large scales.  We provide an overview of the conventional use of radar to observe flying animals and a vision of how radar aeroecology can be further advanced based on existing technology. NEXRAD data are regularly used to track severe weather, estimate rainfall rates, produce wind observations, and deliver other meteorological products. In a similar fashion, radar derived biological products could be produced from bio-scatter and made available to the scientific community and the public. Although the establishment of these products is still an area of on-going research, we will provide examples and make some recommendations.