The New Bedford Whaling Museum's Moby-Dick Marathon is an annual non-stop reading of Herman Melville's literary masterpiece. The multi-day program of entertaining activities and events is presented every January. Admission to the Marathon is free.

Thursday, February 27, 2020

Sunspots & Whale Strandings

Biologists have already demonstrated that many animals can navigate by somehow sensing Earth’s magnetic field lines. Gray whales, which migrate over 10,000 miles a year through a featureless expanse of blue, might be relying on a similar hidden sense.
        - New York Times, 25 Feb. 2020
The Times article quoted above summarizes a study published in Current Biology; a collaboration of Duke University biologists and an astronomer from Chicago's Adler Planetarium. The research looks at strandings of healthy gray whales, chosen because they have "one of the longest migrations of any mammal, an extensive history in the stranding database, and [are] near-shore migrator[s]." (Near-shore is where "small navigation errors increase the risk of stranding.")

Previous studies have correlated these strandings with solar magnetic storms, but were the strandings the result of alterations of the Earth's geomagnetic field, or did the storms somehow "disrupt the animal's receptor itself"?

Examining the influence of climate/season, magnetic field displacement, and radio-frequency noise, the researchers conclude that the whales' navigation errors are "best explained by increases in RF noise rather than alterations to the magnetic field." The analog that comes to mind is headlights of oncoming cars when you're walking at night.

One of the authors, biologist Jesse Granger, notes that such RF noise is not the sole cause of gray whale strandings. Her hope, according to the Times, is "to unlock the secrets of magnetic navigation."

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