Cm. Bergman et Cj. Krebs, DIET OVERLAP OF COLLARED LEMMINGS AND TUNDRA VOLES AT PEARCE-POINT, NORTHWEST-TERRITORIES, Canadian journal of zoology, 71(9), 1993, pp. 1703-1709
We used a combination of faecal pellet analysis and feeding enclosure
trials to determine the diets of collared lemmings (Dicrostonyx kilang
miutak) and tundra voles (Microtus oeconomus) at Pearce Point, Northwe
st Territories. and we looked for evidence of exploitative competition
between the two species. Voles preferred monocotyledons (Carex and Er
iophorum spp.) and lemmings preferred Dryas integrifolia. We found tha
t there was little overlap in the natural diets of the two species, bu
t that overlap was increased experimentally when both species were for
ced to forage in the same habitats. However. food preferences generall
y did not change. The diet of collared lemmings at Pearce Point was si
milar to that found in all other studies except those done in Alaska,
where Dryas is uncommon. We conclude that exploitative competition for
food is unlikely to be an important factor in interspecific relations
between collared lemmings and tundra voles.