Image: © Dom/Stock.adobe.com
Solar storms that bombard Earth from time to time might be throwing grey whales off course by blinding their magnetic sense of direction.
As if marine life wasn’t already under threat from the climate crisis, researchers from Duke University have found evidence showing that the sun might be bringing harm to grey whales.
Writing in Current Biology, the researchers said that the whales may depend on magnetic sense to find their way through the ocean. However, when there are more sunspots and solar storm activity, the whales may become blinded, lose their sense of direction and wash up on beaches.
Magnetic blindness
Sunspots are increasingly linked with solar storms, where sudden releases of high-energy particles from the sun have the potential to disrupt magnetic orientation behaviour when they interact with Earth’s magnetosphere.
As part of this study, the researchers asked whether solar storms are pushing the magnetic field around and giving false directions to the grey whales, or if the solar storms are messing up the receptor itself, effectively blinding them.
“We show that the mechanism behind the relationship between solar storms and grey whales, if it is an effect on a magnetic sensor, is likely caused by disruption to the sense itself, not inaccurate information,” said researcher Jesse Granger.
“The big secondary finding of this paper is that it is possible that the reason the whales are stranding so much more often when there are solar storms is because they have gone blind, rather than that their internal GPS is giving them false information.”
Granger said her interest in long-distance migration stemmed from her getting lost frequently, even on her way to do some shopping.
‘I was flummoxed’
She and her colleagues studied 186 live strandings of grey whales, which showed they occurred significantly more on days with high sunspot counts than on randomly chosen days. On days with a high sunspot count, the number of strandings doubled.
Further research showed that strandings happened more often on days with a high solar radio flux index, as measured from Earth, than on randomly chosen days. Days with high radiofrequency noise saw strandings increase four-fold compared to random days.
“I really thought that the cause of the strandings was going to be inaccurate information,” Granger said.
“When those results came up negative, I was flummoxed. It wasn’t until one of my co-authors mentioned that solar storms also produce high amounts of radiofrequency noise, and I remembered that radiofrequency noise can disrupt magnetic orientation, that things finally started to click together.”
However, Granger stressed there were other potential causes of stranding, such as naval sonar. She now plans to examine several other whale species to see if a global pattern exists.
