Check Out the Beak on This Baby Basking Shark

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BSharks asking questions are wonders of the marine world. This second largest species of living fish can grow up to 40 feet long and weigh over 4.5 tons, all on a diet of plankton. Perhaps because the ocean giants make their living by basking on the surface of the water (thus “basking”) sucking up the smallest animals in the sea, they also have the smallest brain size (weight for weight) of all sharks. I guess you don’t need much street smarts when hunting involves opening your massive mouth and swimming with the krill-filled currents.

As if basking sharks couldn’t be more wonderfully bizarre, they have a rarely appreciated trick up their sleeve: babies that honk extraordinarily.

In 2020, Tyler Greenfield, who identifies as a paleontologist and science writer, published a charming figure of a Japanese Journal of Ichthyology study that shows an 8.5-foot baby basking shark in all its nasal glory.

Researchers captured the curious specimen in the photo off the Pacific coast of Honshu, Japan, in 1977, and estimated the age of the female shark to be less than 6 months old. This chance capture was an unusual opportunity to elucidate an ephemeral feature of basking shark development. “Specimens are rare and growth changes rapidly after birth.[ly]“, wrote the authors.

But the baby basking shark’s impressive nose, which included a groove that ran straight down toward the fish’s palate, isn’t just for show. “Snout structure is thought to be related to juvenile feeding,” the researchers wrote, “during the early free-living stage, when snout shape may increase the efficiency of water flow in the mouth.” They suggested that because a baby basking shark doesn’t quite have the fins of an adult, this specially configured nose helped increase the flow of plankton-containing water into its mouth.

However, baby basking sharks grow quickly and soon grow out of this delicate phase. More recent photos, of a juvenile basking shark feeding off the coast of Scotland, capture a slightly less gonzo-esque version of a baby basking shark’s schnozz, although likely serving the same purpose of directing food into its gaping maw.

Main image: after Izawa, K. and Shibata, T. Japanese Journal of Ichthyology (1993)

• Bob Grant

  Published on October 22, 2025

  Bob Grant is the associate editor of Nautilus.