EPSCoR - Alaska Adapting to Changing Environments

EPSCoR - Alaska Adapting to Changing Environments

Other agencies

Novel wildlife in the Arctic: the influence of changing riparian ecosystems and shrub habitat expansion on snowshoe hares

Warming during the 20th century has changed the arctic landscape, including aspects of the hydrology, vegetation, permafrost, and glaciers, but effects on wildlife have been difficult to detect. The primary aim of this study is to examine the physical and biological processes contributing to the expanded riparian habitat and range of snowshoe hares (Lepus americanus) in northern Alaska. We explore linkages between components of the riparian ecosystem in Arctic Alaska since the 1960s, including seasonality of stream flow, air temperature, floodplain shrub habitat, and snowshoe hare distributions. Our analyses show that the peak discharge during spring snowmelt has occurred on average 3.4 days per decade earlier over the last 30 years and has contributed to a longer growing season in floodplain ecosystems. We use empirical correlations between cumulative summer warmth and riparian shrub height to reconstruct annual changes in shrub height from the 1960s to the present. The effects of longer and warmer growing seasons are estimated to have stimulated a 78% increase in the height of riparian shrubs. Earlier spring discharge and the estimated increase in riparian shrub height are consistent with observed riparian shrub expansion in the region. Our browsing measurements show that snowshoe hares require a mean riparian shrub height of at least 1.24-1.36 m, a threshold which our hindcasting indicates was met between 1964 and 1989. This generally coincides with observational evidence we present suggesting that snowshoe hares became established in 1977 or 1978. Warming and expanded shrub habitat is the most plausible reason for recent snowshoe hare establishment in Arctic Alaska. The establishment of snowshoe hares and other shrub herbivores in the Arctic in response to increasing shrub habitat is a contrasting terrestrial counterpart to the decline in marine mammals reliant on decreasing sea ice.

Data and Resources

  • View website
    Website :: Publisher's website


Status: Complete
Type: Project
Data Types: Report
Primary Contact
Kofinas, Gary
Email: gary.kofinas@alaska.edu
Primary Agency
EPSCoR - Alaska Adapting to Changing Environments

Funding Agency
EPSCoR - Alaska Adapting to Changing Environments

Other Agencies
National Science Foundation

ISO Topics
biota, climatologyMeteorologyAtmosphere

Alaska, Arctic

Direct Record Link
  • 01c8ceef3d596f40f05bf496ca00d929
    Published by Lisa
    2016-09-29 11:15:58 -0800
  • 01c8ceef3d596f40f05bf496ca00d929
    Updated by Lisa
    2016-09-29 11:15:53 -0800
  • 01c8ceef3d596f40f05bf496ca00d929
    New record created
    2016-09-29 11:14:46 -0800