The Great Salt Lake is a vital staging location for waterbirds that migrate through the Pacific Flyway. It is here that over 200 species of birds stop and consume their fill of brine shrimp to continue with their migration southward for the winter. With over half of the North American population staging on the Great Salt Lake, the eared grebes are the largest population of birds during the fall staging period. The Great Salt Lake is an intensively managed resource for humans and animals. It is important to know what areas the birds are more prone to using as to better manage the lake. During their 2-5 month stay, eared grebes undergo a complete molt that renders them flightless. This makes them easy to capture with a gill net on the Great Salt Lake. Over the course of four days, we trapped and banded 58 eared grebes, 26 of which were outfitted with VHF transmitters. Sixteen of those birds were transported to a veterinarian’s office to be implanted with a completely internal transmitter and released at the capture site the next day. The other 10 were outfitted with backpack transmitters and released on the same day of capture. Radio telemetry flights were conducted at least once a week in October and November, but more if the schedule allowed.
Results/Conclusions
Of the 26 birds with VHF transmitters, 12 birds were found twice, and 3 birds were detected multiple times. Only birds with implant transmitters were detected multiple times. Five birds with backpacks were detected twice. Over a period of two months, only one mortality was detected. It was suspected to have been predated because there was no body found, only the transmitter and the metal leg band. The lakes large size hindered us from gathering more location points. The largest, straight-line distance traveled by an eared grebe on the Great Salt Lake during the fall of 2017 was 39.4 kilometers over a period of 12 days. Some grebes were detected in the same area of the lake that they were captured and released, while some traveled to opposite ends. This data has provided a basic understanding of the movements of eared grebes on the Great Salt Lake; however, a larger sample size and GPS transmitters could provide a deeper understanding of the population dynamics and any patterns of movement on the Great Salt Lake.