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Posted by A & M on 19:15:55 10/01/10
In Reply to: Great Black-Hawk: Virginia Key posted by Robin
Robin we noted the increase in dragonfly yesterday as the birds came in. While looking at loads of swallows coming in off the water we observed waves of dragonfly simultaneously. We noted that 90% of the dragonfly were Wandering gliders a worldwide traveler.
Dragonfly and other animal biota can be picked up by radar. The radar is pretty sensitive and can even pick up smoke, pollen and other windblown particles. This is why we use the velocity (red/green) images a whole lot more than the reflectivity (blue) images. By using the velocity images we can determine direction as well as the speed of the signatures on radar. When we look at the velocity animations we look for objects that are moving at speeds greater to the wind speed. These returns are typically attributed to bird movement as they fly faster than the wind. Dragonfly movement would typically move along with the wind speed.
We feel that a good number of the returns present during the day could have been swallows, waders and even some raptors. Rafael mentioned large numbers of Cliff Swallow today at Curry Hammock SP, plus lots of other daytime movement such as Anhinga in groups of ~60 at a time!
Nature is Awesome
Angel & Mariel
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