Terns are seabirds in the family Laridae that spend most of their lives in offshore oceans and only come to land during the breeding season. Therefore, when compared with other avian groups, it is relatively challenging and difficult to study seabirds. There are 12 tern species in Hong Kong according to the list of birds in Hong Kong, and only three of them breed locally as summer visitors. They are Bridled Tern, Black-naped Tern, and Roseate Tern.

With sponsorship from Swire Trust, the Hong Kong Bird Watching Society launched a tern satellite tracking project in Aug 2022. Our research team attached a satellite tracking device by Argos System to the Bridled Tern (Leg flag: CV) to observe its migration route in real-time.

Before the attachment, our researchers evaluated the bird's physical and health condition in detail and ensured that the weight of the device is not more than 3% of the bird's weight. As the roosting site of the tern is rocky coasts of islands instead of an open area, the satellite tracking device must be flexible enough and was modified to adapt to extreme environment. The installation process is supervised and executed by experienced researchers. Birds are captured and attached with satellite trackers in the most friendly and safe way to minimize the impact on them. The satellite tracking device is maintained by solar panels and will automatically fall off after a period of time.

We will keep updating CV’s locations, please follow our social media platforms (Facebook、Instagram) and search #TernTracking hashtag.

Project sponsored by Swire Trust