August 10, 2012
Climate Change Altered Hibernation For Rocky Mountain Animal Species
redOrbit Staff & Wire Reports - Your Universe Online
For a species of Rocky Mountain ground squirrel, climate change is causing a late wake-up call from hibernation and the effect is deadly.
Examining data on a population of Columbian ground squirrels, a University of Alberta-led international research team found a trend of late spring snow falls has delayed the animals' emergence from hibernation by 10 days over the last 20 years.
"Columbian ground squirrels are on a tight schedule; Females mate four days after emerging from hibernation. They give birth 24 days later. The newborns are nursed for 28 days, and then they're on their own, explained Jeff Lane who is a U of A Evolutionary Ecologist.
"Losing just 10 days during their short active period reduces their opportunity to eat enough food so they can survive through the next hibernation period of eight to nine months," said Lane.
Research shows there's little wiggle room in the life cycle of the ground squirrel. The period of plant growth, which is their food supply, last only 3 to 4 months on their home turf in the Rocky Mountains.
"Our data shows that over the life of the study, the survival rate of adult females has fallen by 20 per cent and much of this could be due to late emergence from their burrows brought on by late spring snowfalls," said Lane. "The researchers say the study area's population has gone from one of growth 20 years ago to its current state of just maintaining population stability."
The study area is in a sub-alpine meadow west of Calgary and consists of a 200-metre by 400-metre block. The study area was set up in 1992 by U of A biologists. The data was collected through observation and by trapping and releasing all the ground squirrels in the study area to monitor their condition, Lane said.
Lane's hibernation study began five years ago and collaborated with researchers in Scotland, France and the U of A. Lane was the lead researcher on the paper that was published August 8, in the online edition of the journal Nature.