Saturday, August 20, 2011

Range Shifts Linked to Climate Change

Red-banded Hairstreaks are expanding northward.
Many studies over the past decade have tried to document how animals adapt their ranges in response to a warmer climate. A recent paper analyzed data from over 50 such studies to get a sense of the bigger picture.
The findings indicate that among the plants and animals tracked in the studies, species over all were escaping to higher elevations at an average rate of 36.1 feet per decade and moving away from the equator at a rate of 10.1 miles per decade. That’s a steady march poleward of eight inches per hour. Those two rates are respectively two and three greater than those found in the last similar meta-analysis in 2003.

The data also clearly indicates that the species changing their distribution the most rapidly are those in regions where the most warming has occurred.

While the study pulled together literature from around the world, the vast majority of available research comes from Europe and North America, leaving big holes in global understanding how species in one of the most biologically rich areas, the tropics, are responding to climate change.

These unanswered questions are further complicated by the primary role of precipitation, as opposed to temperature, in distributing most species in the tropics. The precise effects of climate change on precipitation are still a source of debate and uncertainty.