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This is scientific Americans 60 second science. I'm Jason Goldman.

The image of a dorsal fin cutting through the sea surface is iconic, but scientists studying the stomach contents of young great white sharks off the coast of Australia were in for a surprise when they learned that the predators seem to spend a lot of time patrolling the sea floor.

They have a predominantly fish-based diet which is not unexpected for juvenile white sharks.

The most important prey species we identified was East and Australian salmon.

University of Sydney graduate student Richard Granger.

He and his team sorted through the stomach contents of more than 50 juvenile

white sharks that died after being entangled in shark exclusion nets meant to protect swimmers.

The overall unexpected finding was just the diversity and importance of bottom-dowing species,

things like stargazers, which bury themselves in the sand.

They're quite strange-looking fish and flat-haired, but also stingrays. the As Granger points out, the sharks enjoy protections throughout the world.

So most researchers estimated their diets through the chemical markers that they can ethically access

by taking small skin samples.

These measurements indicate at what level by taking small skin samples.

These measurements indicate at what level of the food chain the predator is feeding,

but not the actual critters that make up their meals.

There's quite a lot of evidence that lots of different animals so even carnivores omnivores

herbivores they'll select different prey or food based on a particular balance of nutrients.

Ranger hopes that by further understanding what juvenile white sharks like to eat, he can

begin to piece together how and why they make their predatory choices.

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