(IVAR) - Final Report - Strategic Environmental Research and ...

2 TECHNOLOGY/METHODOLOGY DESCRIPTION
2.1 TECHNOLOGY/METHODOLOGY OVERVIEW
There have been dramatic and rapid developments in avian radar technologies during the past
decade. Avian radars have gone from analog systems without the capability of automatically
recording data to systems with digital signal processing and the capacity to automatically save
data to hard drives. Figure 2-1 provides a chronological overview of the development of avian
radar systems.
Radar has been used to study birds since the 1940s, shortly after the technology was developed
(Lack, & Varley, 1945). More recently, researchers began using Doppler weather radars in the
1990s to study bird movement on regional and continental scales (100 km and beyond). During
this same period, researchers assessed how airport surveillance radars, which can also detect
birds, might fill in the medium-range scales (10-100 km) of bird movements. In both of these
cases, however, the radars used were designed for some other application (e.g., weather
prediction, air traffic control), they were not necessarily located where the birds of interest were,
and they were too costly to purchase, integrate, and dedicate to studying birds.
Figure 2-1. Chronology of avian radar developments. [Source: Nohara, et al., 2007]
Beginning in the 1970s, researchers have adapted analog marine radars in order to study bird
movements. Human operators developed procedures to manually identify bird echoes on the
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