Global Warming

Global Warming Pushing Alpine Species Upslope

For every one-degree-Celsius increase in temperature, mountaintop species shift upslope 100 meters, shrinking their inhabited area and resulting in dramatic population declines, new research by University of British Columbia zoologists has found.

The study, a first-of-its-kind broad review, analyzed shifts in elevation range in 975 populations of plants, insects and animals.

Most mountaintop species we looked at are responding to warming temperatures by shifting upslope to live in cooler environments. As they move towards the mountaintop, the area they live within gets smaller and smaller. This supports predictions that global warming could eventually drive extinctions among species at the top.

The study found that most mountaintop species have moved upward, including:

- The northern pocket gopher in Nevada's Ruby Mountains lost more than 70 percent of its inhabited area over the past 80 years as a 1.1-degree temperature increase drove populations upslope.

- The mountain burnet butterfly in the French Pyrenees adjusted to a one-degree temperature increase by shifting upslope 430 meters, losing 79 percent of its range over the past 50 years.

- An alpine meadow flower in the Himalayas moved upslope more than 600 meters as temperatures rose more than 2.2 degrees in the past 150 years. It lost 29 percent of its habitat in the region.

The research also found that a few species, such as the white-crowned sparrow in the southern Sierra Nevada mountains in California, moved their entire range down mountains.

"This highlights how complicated responses to climate change are likely to be”, said the study authors.