A new study published in the journal Science says that due to climate changes polar bears might be faced with starvation as the ice melts during the summer and they are not able to adapt their metabolism to low food supplies.
The research team from the University of Wyoming in Laramie used satellite collars and monitors which were surgically implanted in order to keep track of the core body temperatures of the polar bears both on ice and on the shore and to monitor the animals’ movements during summer. 25 polar bears from Beaufort Sea and Alaska were observed for more than two years.
According to zoologist Merav Ben-David polar bears are unable to adapt their metabolism to low food supplies in summer even though they can do this in winter. During winter time they can reduce their metabolism because it is something which is part of the hibernation process. He compared this process to what happens when one turns down the thermostat inside ones house in order to conserve heating and energy mentioning that in this chase it is a physiological mechanism.
Researchers assumed that since polar bears can reduce their metabolic rate during winter time they can also do it during summer, but it seems that this is not true. When the metabolic rate is reduced the body temperature of the bears drops between 39 and 35 degrees and can remain like this for whole months. Since during summer polar bears go through long periods of time without food researchers expected them to reduce their body temperatures, but this did not happen.
John Whiteman, one of the researchers involved in the study, said that the animals cannot rely on the energy which they store and this indicates that they are vulnerable to lost hunting opportunities. He also remarked:
“This suggests that bears are unlikely to avoid deleterious declines in body condition, and ultimately survival, that are expected with continued ice loss and lengthening of the ice-melt period.”
What is needed now in order to stop this trend is a quick change of the perspective on climate change. Nevertheless it might however be too late anyway.
Image Source: lifeonthinice.org