Observations of Gray Fox Urocyon cinereoargenteus (Schreber, 1775) (Mammalia: Carnivora: Canidae) denning behavior in New Hampshire, USA

Abstract

Dens are important for mammals because they provide protection for dependent young from weather and predators. Gray Foxes Urocyon cinereoargenteus are an understudied mesocarnivore that range across North and Central America, and have limited information available on demographics and denning behaviors. We monitored a Gray Fox den in New Hampshire over the course of three years (2017–2020) to quantify behaviors and document visitation and activity patterns of Gray Foxes and other mammal species. We observed Gray Fox pairs intensively using the den during parts of the first and second years of the study. Across the 949 trap nights over which we monitored the den, use by adult Gray Foxes peaked in spring – coinciding with the pup-rearing season. During this time, the adults were diurnal with peaks in the afternoon, opposed to being crepuscular at other times of the year. We did not observe any puppies during the first breeding season, but during the second year we documented a puppy emerging from the den on 24 May 2018. All excursions by the puppy outside the den for the first five days were restricted to the immediate area near the den entrance and the puppy was always with an adult when outside the den. During the puppy’s second solo excursion, however, we documented a Bobcat Lynx rufus pounce and kill the puppy, after which the adults abandoned the den. We also observed the common (squirrels and rabbits) and uncommon (a bat) prey items brought to the den, and the den being shared among multiple species. Our observations highlight the importance of dens for protecting young, and our observations of visitation and activity patterns, as well as common and uncommon prey, help inform our understanding of the denning behavior of Gray Foxes.