My ping is normally at 140ms and it hovers around that for most of my game play, but recently any time I go near anything classed as hostile, bears, coyotes, revenants etc, my ping shoots to over 600ms and yoyo's up and down like crazy, once I get out of range of the mob it settles back to it's normal 140ms.

The other mobs like cats, dogs and rabbits have little to no effect on the ping.