Unexplained Rotation in the Graph of a Home Range?

[Jared Zev Kannel]

Hello Dr. Fleming,

I am trying to plot the home range of a bison named Envis. For other bison, I am plotting the home ranges based on all of their telemetry points, as well as one plot for their points in the summer and one plot for their points in the winter. Envis only has points in the summer, so when I plot the "total" home range and the "summer" home range, they should be the same. For the following to chunks of code, I obtained the same variograms and the same home range size estimate in square kilometers:

However, this is what I get for the plots:

They are the same shape, same size, but about a 45 degree rotation away from being identical. This inconsistency makes me nervous about all of the other animals that have both winter and summer points. Do you know why I'm getting this inexplicable rotation between two graphs that should be identical?

Thank you,

Jared Kannel

[Christen Fleming]

Hi Jared,

Did you import the data two different ways? What does projection() say on the two telemetry objects?

Best,

Chris

[Jared Zev Kannel]

I created the summer and winter telemtry objects by subsetting the initial movebank imports. When I use the projection on my telemetry objects, this is what I get:

[Christen Fleming]

Hi Jared,

Subsetting before as.telemetry() gave different automated projections. You can just do

projection(winter_bison_data) <- projection(bison_data)

projection(summer_bison_data) <- projection(bison_data)

before analysis and that should fix everything.

Best,

Chris