Summer Movements and Impact of Individual Striped Skunks, Mephitis mephitis, on Duck Nests in Saskatchewan


  • Serge Larivière Delta Waterfowl Foundation, R.R. 1, Box 1, Site 1, Portage La Prairie, Manitoba R1N 3A1
  • Lyle R. Walton Wildlife Research and Development Section, Ontario Ministry of Natural Resources, Ontario Government Complex, Hwy 101 E., P.O. Bag 3020, South Porcupine, Ontario P0N 1H0
  • François Messier Department of Biology, University of Saskatchewan, 112 Science Place, Saskatoon, Saskatchewan S7N 5E2



Striped Skunk, Mephitis mephitis, duck, movement, nest predation, prairie, predator ecology, Thickwood Hills, Saskatchewan


Striped Skunks (Mephitis mephitis) are important predators of duck eggs in the Canadian prairies. We estimated the impact of individual Striped Skunks on duck nests by intensive observations of foraging movements and depredation of duck nests in southern Saskatchewan, 1993-1994. Nightly, skunk movements were variable (range 0-20 km per night), and did not differ among seasons for females, or between males and females during the parturition/rearing season. Overall, nightly movement of Striped Skunks averaged 7.4 km for females (SD = 5.9 km, n = 20 females) and 6.7 km for males (SD = 3.2 km, n = 5 males). During 1,873 h of radio-tracking, we observed depredation of 10 duck nests by 8 skunks (7 F, 1 M). Using our observed estimate of one depredation for every 187 h, and averaged nightly activity of 8-10 h per night, we estimated that individual skunks find one duck nest every 19-23 nights. Thus, during the 60-day nesting season for ducks (mid-May to mid-July), individual skunks probably find 2-3 duck nests. These observations reinforce the growing evidence that, at normal duck nest densities (<2.5 nests/ha), depredation of eggs by Striped Skunks is opportunistic, and the impact of Striped Skunks on duck nests is a direct function of Striped Skunk abundance.