Aristotle on Strandings
Dolphins live together in pairs, male and female. It is not known for what reason
they run themselves aground on dry land; at all events, it is said they do so at times,
and for no obvious reason.1
Aristotle wrote this around 350 BCE. He didn't know then why marine mammals strand themselves. Based on the current science, we still don't know 24 centuries later.
In 50 BCE, Pliny the Elder wrote about a killer whale that had stranded in a harbor near Rome. Unlike Aristotle's dolphins, there was an obvious reason for the whale's stranding. According to Pliny, the whale was eating "certaine beasts hides that were brought out of Gaule, and were cast away and perished by the way." Pliny explains that the whale was so busy eating carcasses cast overboard that it got itself stuck in the sand and couldn't get itself unstuck.2
In 1577, Johannes Wierix, a Dutch artist, made an engraving of three beached whales. The engraving does not give any reason for the stranding, if anyone knew. Based on the engraving, the local humans were too scared and too busy fleeing the beached whales to ask.3
According to the National Oceanic and Atmospheric Administration, the first reported pilot whale stranding in the United States was at Cape Cod in 1620. The NOAA report states that "pilot whale strandings were common in Cape Cod Bay during the 17th century." Many of the strandings were attributed to drive fishing by whalers, but 20 were not.4
The point of this historical exercise is that marine mammals have been stranding themselves for as long as man has been recording scientific observations. No one knew the cause of stranding in Aristotle's day, and no one knows now. There may be multiple causes.
The current focus on anthropogenic sound as the cause for marine mammal strandings may not end them. Further investigation into other stranding causes may be necessary to solve the problem. This further investigation should include reliable research into the effects of anthropogenic sound on marine mammals, and into what percentage of strandings can accurately be attributed to anthropogenic sound. To help achieve this goal, the National Marine Fisheries Service should issue research permits that enable dose response studies that accurately establish acoustic threshold effects on marine mammals
1Aristotle, Historia Animalia, Book IX, Ch. 48 (translated by D'Arcy Wentworth Thompson).
2C. Plinius Secundus, The Historie of the World, Book IX, Ch. 6 (Philemon Holland, translator 1601).
3Click here to see the engraving.
4The NOAA report is available online at. The strandings discussion begins at page 3. Click here.