Each year, grey whales travel more than 16,000 kilometres along the Pacific Coast, from Mexico to Alaska and back. But every so often, many of them become stranded. Now a new study suggests these strandings could be linked to solar storms.
Each year, grey whales travel more than 16,000 kilometres along the Pacific Coast, from Mexico to Alaska and back. But every so often, many of them — sometimes hundreds — become stranded.
It’s not completely clear how grey whales navigate the depths of the ocean during this long journey, but one hypothesis is they use Earth’s magnetic field as a sort of road map.
Now a new study, published in the journal Current Biology, further supports that hypothesis, going so far as to suggest the reason for the mass strandings could be linked to solar storms and how that activity affects Earth’s magnetic field.
The sun and Earth
The sun’s activity doesn’t take place in isolation; Earth — in fact, every planet in the solar system — is affected by it.
One form of solar activity comes in the form of sunspots, the darker, cooler regions that form on the sun’s surface.
Sunspots have magnetic field lines that can become entangled, like an elastic band, and can snap, releasing a solar flare. These flares produce large eruptions of electromagnetic radiation that can last from minutes to hours.
Travelling at the speed of light, if one of these eruptions reach Earth, it can cause radio blackouts. They also affect animals.
Many species, such as lobsters, frogs and snails, use magnetoreception — or a sense that allows them to use the Earth’s magnetic field — for navigation.
There could be two ways in which animals can sense a magnetic field.
One is they have magnetite particles somewhere in their bodies,