Dartmouth scientists study pine beetle population dynamics
By Summit Voice
SUMMIT COUNTY — Dartmouth scientists say they may have found a pathway to keeping pine beetles in check, showing that their populations fluctuate between extremes, with no middle ground.
“That is different from most species, such as deer, warblers and swallowtail butterflies, whose populations tend to be regular around some average abundance based on food, weather, and other external factors,” said Matt Ayres, a professor in the Department of Biological Sciences at Dartmouth and senior author on the paper. “They don’t appear and disappear in cycles. Rather, they exist in two stable equilibrium states—one of high abundance and the other of scarcity.”
Once the population pendulum swings toward the high end, it won’t quickly or easily swing back, Ayres explained.
According to the new study, forest managers might be able to keep pine beetle populations at the low end of the scale by boosting competitor and predator beetle populations — but they don’t address how that could affect the overall equilibrium of forest ecosystems, especially those where older trees need a change agent like bark beetles to spur regeneration. Continue reading