Washington: Climatic change between now and 2100 will change more than 100 times faster than the rate at which the species can acclimatise, a new study has suggested.
According to the study by Indiana University researchers, which focuses on North American rattlesnakes, rate of future change in suitable habitat will be two to three orders of magnitude greater than the average change over the past 300 millennia, a time that included three major glacial cycles and significant variation in climate and temperature.
“We find that, over the next 90 years, at best these species’ ranges will change more than 100 times faster than they have during the past 320,000 years,” said Michelle Lawing, lead author of the paper.
“This rate of change is unlike anything these species have experienced, probably since their formation.”
The researchers made use of the fact that species have been responding to climate change throughout their history and their past responses can inform what to expect in the future.
They synthesized information from climate cycle models, indicators of climate from the geological record, evolution of rattlesnake species and other data to develop what they call ‘paleophylogeographic models’ for rattlesnake ranges.
This enabled them to map the expansion and contraction at 4,000-year intervals of the ranges of 11 North American species of the rattlesnake genus Crotalus.
Projecting the models into the future, the researchers calculated the expected changes in range at the lower and upper extremes of warming predicted by the Intergovernmental Panel on Climate Change — between 1.1 degree and 6.4 degrees Celsius.
They calculated that rattlesnake ranges have moved an average of only 2.3 meters a year over the past 320,000 years and that their tolerances to climate have evolved about 100 to 1,000 times slower, indicating that range shifts are the only way that rattlesnakes have coped with climate change in the recent past.
With projected climate change in the next 90 years, the ranges would be displaced by a remarkable 430 meters to 2,400 meters a year.
The findings suggest that snakes would not be able to move fast enough to keep up with the change in suitable habitat. The authors have also insisted that the creation of habitat corridors and managed relocation may be needed to preserve some species.
The study has been published by the online science journal PLoS One.
ANI
