Assessment of potential impacts to avian species from a proposed 750 foot guyed tower at NASA’s Goddard Space Flight Center’s Wallops Flight Facility on Wallops Island, Virginia

• NASA has proposed A 750 foot guyed instrumentation tower to be constructed on Wallops Island, VA at one of two locations. • Wallops Island is embedded within a critical location along the Atlantic Flyway that supports millions of avian species annually, many of which are of conservation concern. Since this tower has the potential to act as a collision hazard for birds, NASA has requested a synthesis of existing information on the species exposure and relative vulnerability to the proposed construction. • The proposed tower site and its alternative are relatively identical with respect to location from shoreline or other natural habitats use by birds and are only separated by 2,300 feet. There is no indication from known information that one site or the other poses any greater or lesser risk to collision by birds. • While the construction of an instrumentation tower on Wallops Island may result in bird mortality collisions, a central question from a population perspective, is not how many individuals would be killed annually but if the focal population would be able to sustain the mortality incurred and still reach conservation and management objectives. • Information required to make a full assessment on an expected mortality rate from the proposed tower does not exist. Information required for this type of assessment would include full understanding of the distribution of migrant corridors, breeding populations, winter populations and the flight altitudes of many species. In many cases this is only possible through post-construction monitoring. Because this monitoring data does not exist, the best assessment, based on the information available, was undertaken to provide relative levels of risk based on characteristics of broad population overlap with the tower site and species flight and behavioral characteristics