Full paper: https://sci-hub.se/downloads/2020-02-04/2c/10.1007@s10393-02...

This presents some alternate hypotheses for the outbreak and claims Anthrax is fairly unique in its ability to survive repeated freeze-thaw cycles.

Thanks for pointing that out. For the unfamiliar (like me a few seconds ago) culling means "to reduce or control the size of (something, such as a herd) by removal (as by hunting or slaughter) of especially weak or sick individuals " [1]

[1] https://www.merriam-webster.com/dictionary/cull