"The big unknown is how long this buffering effect will last," Hunter said. "Will it keep going indefinitely, or will the negative effects of climate change eventually just override these buffers, causing the moth populations to collapse?"
Another big unknown: What ecological forces are currently buffering the Lapland moths from the negative effects of a warming climate?
Finnish team members who've been collecting moths at the Vrri reserve for decades say they have noticed a gradual increase in tree and shrub density, increased rates of tree growth, and a rise in the altitude of the tree line.
Trees provide food and shelter for moths, and leaf litter offers overwintering sites and resting areas away from predators. Perhaps the observed vegetation changes are helping to offset the negative effects of warmer temperatures and increased precipitation. That possibility was not analyzed in the current study.
|Contact: Jim Erickson|
University of Michigan