Can you believe that our Purple Martin roost is visible on radar? You have to go to a website with unfiltered radar, such as rap.ucar.edu. You can also pick out other roosts scattered around the Southeast.
Below are images from this morning, first the Slidell and then the Mobile radars.
The above image is the Slidell site. The main light blue blob is meaningless scatter near the radar installation. The blobs at the north and south end of the Causeway are the departing martins a few minutes before 6 AM. There appear to be more at the north end of the bridge than the south end, though there may be an effect of being a bit closer to the radar so the beam is lower and catches more birds. You may have noticed that the north end of the bridge has martin fences to avoid car impacts, just like the south end- but farther from shore.
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