Habitat alteration by geese at a large arctic goose colony: consequences for lemmings and voles

• Published in: Canadian Journal of Zoology
• Main Authors: Samelius, Gustaf, Alisauskas, Ray T.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 2009
• Subjects: Arctic; Karrak Lake; Nunavut
• Online Access: http://dx.doi.org/10.1139/z08-140; http://www.nrcresearchpress.com/doi/full-xml/10.1139/Z08-140; http://www.nrcresearchpress.com/doi/pdf/10.1139/Z08-140

Heavy grazing by Ross’s geese ( Chen rossi (Cassin, 1861)) and lesser snow geese ( Chen caerulescens (L., 1758)) has resulted in substantial habitat alteration in some parts of the Arctic. However, the influence of these habitat alterations on other animals is poorly understood. We therefore examined how habitat alteration by geese influenced small-mammal (lemmings and voles) abundance at the large goose colony near Karrak Lake, Nunavut, by comparing small-mammal abundance and aboveground biomass of plants inside and outside the colony. Heavy grazing by geese resulted in virtually complete removal of graminoid plants (grasses and sedges) in lowland areas in the colony, which in turn was associated with a reduction in small-mammal abundance of about one order of magnitude compared with that in lowland areas outside the colony. Aboveground biomass of plants in upland areas in the colony was also reduced compared with that in upland areas outside the colony, although this reduction was less pronounced than that in lowland areas in the colony. Moreover, this reduction was not associated with a reduction in small-mammal abundance. There was, thus, a strong negative correlation between habitat alteration by geese and distribution and abundance of small mammals at this colony.