While downloading the oystercatchers’ location data is showing us patterns of movements and how much habitat they use, we also found on our most recent download that CF7 has followed Arnie’s lead and is no longer transmitting, flying the coop, so to speak. And, unfortunately, she had just done something interesting before losing the transmitter. She took a flight from her territory on South Core Banks west across Pamlico Sound to the Davis, NC area. There she stopped at a small bay called Jarrett Bay (maybe it looked like the photo to the right) and then flew back to South Core Banks. Why? Was she starting to get restless in preparation for migration? Is she ready to find a different roost site for fall and winter? Did she just feel like taking a trip?
We don’t know if CF7 the harness holding the transmitter on simply gave out, or if something else has happened. But, we do know that her satellite has stopped transmitting. If a bird drops its transmitter, unless the device lands with its solar panels facing upwards, it will discharge its battery in a day or so and go dark. If it is facing the sun, it may still transmit, but it will also send another signal, indicating that it has not moved. A small motion detector in the transmitter can tell if the unit has moved or not, such as when the bird’s natural motion jiggles it. Of course, if the bird carrying the transmitter dies for some reason, it will also stop moving and face the same trouble charging its batteries.
Although it’s unlikely, it’s possible that something has happened to CF7. Peregrine Falcons begin to migrate in late August, arriving with the first weak cold fronts and needing fuel for their own journeys. So one threat that faces American Oystercatchers and other shorebirds is a hungry raptor. But, CF7 is an adult bird in good health. She stands an excellent chance of simply having escaped her transmitter’s harness and is likely flying free like the oystercatchers to the right. And, fortunately, Cape Lookout National Seashore, her chosen breeding ground, is monitored every year for beach-nesting birds, and if and when she returns to her territory, a biological technician will spot the new bands we placed on her legs, report CF7 to the oystercatcher band database, and we’ll know she’s made it back safe and soundjust without one very useful piece of hardware.