Recently discovered whale feeding behaviour may have been observed in ancient texts. 

New research suggests that a mysterious whale feeding behaviour, only recently documented by scientists in the 2010s, has been described in ancient texts about sea creatures as early as two millennia ago. 

The feeding technique, termed “tread-water feeding” in Bryde’s whales in the Gulf of Thailand and “trap-feeding” in humpback whales off Canada’s Vancouver Island, involves whales positioning themselves vertically in the water with their jaws open at right angles, waiting for fish to swim into their mouths. 

Scientists believe that the technique’s success is due to the instinct of fish to shoal towards the apparent shelter of the whale’s mouths. 

Flinders University scholars have identified multiple descriptions of the behaviour in ancient texts, including a mid-13th-century Old Norse text called Konungs skuggsjá (the King’s Mirror), where the creature hafgufa is described as keeping its mouth open for a time, catching and hiding prey that had come seeking food. 

In the Naturalist – a 2,000-year-old text that “preserves zoological information brought to Egypt from India and the Middle East by early natural historians like Herodotus, Ctesias, Aristotle and Plutarch” – the ancient Greeks refer to a creature known as aspidochelone.

The text reads: “When it is hungry it opens its mouth and exhales a certain kind of good-smelling odour from its mouth, the smell of which, once the smaller fish have perceived it, they gather themselves in its mouth. But when his mouth is filled with diverse little fish, he suddenly closes his mouth and swallows them.”

The researchers noted that the lack of scientific observations prior to the last two decades might be explained by the relative rarity of this feeding strategy or because the strategy was not being used. 

The study was published in the journal Marine Mammal Science.