The project lead for the collection of this data was Erin Zulliger. Elk (12 adult females) were captured and equipped with GPS collars (Litetrack/Pinpoint Iridium collars, Lotek Wireless Inc., Newmarket, Ontario, Canada or Vectronic Aerospace) transmitting data from 2016-2023. The East Shasta Valley herd migrates between traditional summer and winter seasonal ranges, and migration corridors, migration stopovers, and winter ranges were modeled separately for this herd, but are not a part of this analysis. Annual home ranges were modeled using year-round data to demarcate high use areas. GPS locations were fixed at 1-13 hour intervals in the dataset. To improve the quality of the data set, the GPS data locations fixed in 2D space and visually assessed as a bad fix by the analyst were removed.The methodology used for this migration analysis allowed for the mapping of the herd’s annual range. Brownian bridge movement models (BBMMs; Sawyer et al. 2009) were constructed with GPS collar data from 12 elk, including 36 annual home range sequences, location, date, time, and average location error as inputs in Migration Mapper. BBMMs were produced at a spatial resolution of 50 m using a sequential fix interval of less than 27 hours. Home range is visualized as the 50th percentile contour (high use) and the 99th percentile contour of the year-round utilization distribution. Annual home range designations for this herd may expand with a larger sample.
