Are solar storms causing whales to beach themselves?On September 11, 2017 by Kenna
A new study in the International Journal of Astrobiology posits that beached whales may sometimes be influenced by solar storms. A team led by Klaus Heinrich Vanselow writes:
Mass strandings of whales have often been documented, but their causes and underlying mechanisms remain unclear. We investigated the possible reasons for this phenomenon based on a series of strandings of 29 male, mostly bachelor, sperm whales (Physeter macrocephalus) in the southern North Sea in early 2016. Whales’ magnetic sense may play an important role in orientation and migration, and strandings may thus be triggered by geomagnetic storms. This approach is supported by the following: (1) disruptions of the Earth’s magnetic field by Solar storms can last about 1 day and lead to short-term magnetic latitude changes corresponding to shifts of up to 460 km; (2) many of these disruptions are of a similar magnitude to more permanent geomagnetic anomalies; (3) geomagnetic anomalies in the area north of the North Sea are 50–150 km in diameter; and (4) sperm whales swim about 100 km day−1, and may thus be unable to distinguish between these phenomena. Sperm whales spend their early, non-breeding years in lower latitudes, where magnetic disruptions by the sun are weak and thus lack experience of this phenomenon. ‘Naïve’ whales may therefore become disoriented in the southern Norwegian Sea as a result of failing to adopt alternative navigation systems in time and becoming stranded in the shallow North Sea.
Via an in-depth article on the topic by Sarah Laskow:
The whales found stranded in the North Sea have always been males because of the differences in how male and female whales live. Sperm whales breed in equatorial oceans, and young whales remain in those waters with their mothers for at least a few years, and sometimes well into adulthood. After leaving their mothers, male whales form groups of their own, which travel far from the breeding waters. Sperm whales share our taste for squid, and the bachelor groups follow them north. The groups the bachelor whales form are not always tight-knit, but still they can lead each other into trouble.
Image: Richard Humphrey