Correlating Differences Between Life-History Stages of Trumpeter Swans Using Behavioral and Accelerometer Data
The Interior Population (IP) of Trumpeter Swans results from relocation of individuals from several source populations. As part of a larger project evaluating movement ecology and genetics of the re-established IP population, we collected observations on transitional stages (e.g., incubation to brood rearing) of 32 GPS-collared swans. We paired these observations with accelerometer data to assess whether life-history stages could be determined from remotely derived data alone. We also conducted longer duration (6-minute scan) behavioral observations of 4 GPS-collared swans in the Twin Cities area to compare behavior between IP swans and swans in an extant population (the Interior Alaska population). Association between overall dynamic body acceleration (ODBA: an index of energy expenditure) and transitional stage was highly variable across 4 swans, although some ODBA data indicated a clear differentiation between different life-history stages. Based on direct observation, behavior of IP swans differed from that of Interior Alaska swans, although the potential reasons for these differences are not clear. Further assessment of factors influencing potential differences in behavior of IP and Interior Alaska swans as well as assessing behavioral status of swans from telemetry data is likely necessary.