One of my personal projects this winter was following the activity recorded on game cameras at two different porcupine dens—one in a huge, hollow, standing sugar maple, and the other beneath the root-ball of a partially tipped-over hemlock (which we visited in this Outdoor Radio episode). I was primarily interested to see how frequently, if at all, fishers (and other predators) visited the dens. Although fishers are often touted as porcupine predators, in my experience from years of snow-tracking fishers, following radio-tagged individuals, and analyzing scats, porcupines make up a very small percentage of their diet, and some fisher probably never taste porcupine. My game-cam footage appears to support that as well.
After five months of camera “trapping,” I captured countless videos of porcupines leaving and returning to their dens, a couple visits by fox, coyotes, turkeys, raccoons, deer, and snowshoe hare, but just two fleeting fisher visits, one at each den. The video below, recorded on 3 Feb. 2021 (the date and time on the camera was incorrect), shows the fisher arrive, give the den tree a quick sniff, and continue on his way.
The second video (below), a rare daylight capture of a mostly nocturnal predator, shows the fisher (probably a male based on his large size), lope up behind the den, then descend to the entrance using the porcupine’s own footprints, and briefly investigate before moving on. The porcupine, safely inside, had returned to the den just a few hours earlier.
Of course, fishers are opportunistic predators, and their only chance of killing a porcupine is to find one in the open where it cannot protect its vulnerable face. So, in that regard, visiting a den site may not be the most successful tactic if porcupine is to be on the menu.
One of the more interesting game-cam captures occurred on the evening of 20 Feb. 2021. This was a day after sleet and freezing rain turned the deep, soft powder that had persisted since mid-January to a firm, solid crust. After more than a month of trudging through ever-deepening snow to get from its den site to its feeding area in a nearby hemlock stand, the porcupine seems to be dancing for joy, or perhaps testing the traction on the now firm, slippery substrate. However, a more likely explanation is that this apparently young porcupine (based on its small size), probably got a whiff of a potential predator that passed by the area (but beyond my camera’s range) sometime before the “porky” left its den site. With quills erect, it appears to be reacting to a threat that is everywhere but nowhere at the same time, before finally hustling off to the security of a hemlock tree.