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Sharks: Different species hunt at different times in Gulf of Mexico

Shark fin.Image source, Getty Images

Sharks living in the waters in the Gulf of Mexico have a hunting timetable.

It was previously thought that sharks hunted at the same times - around sunrise and sunset - but new research has shown that different species of shark, that share the same living space, eat at specific times to avoid food shortages and getting in each other's way.

Experts looked at the behaviour of six coastal shark species. They tagged a total of 172 individual animals and monitored their activity levels over time, which totalled 3766 hours of data!

The feeding timetable surprised the researchers because sharing resources isn't usually common in nature among other animals that live in the same space. However the team monitoring the sharks now think this kind of behaviour could happen more often among marine animals.

"This could be more common than we think," said Karissa Lear who has been monitoring the activity of the sharks.

"Marine ecosystems haven't been widely studied in this way because tracking and observing underwater animals can be more difficult."

What is an ecosystem?

A community of animals, plants and microorganisms, together with their habitat is called an ecosystem.

For example, a pond ecosystem may consist of a pond habitat, inhabited by aquatic plants, microorganisms in the mud at the bottom, fish in the water and a heron on the bank.

The timetable: Who eats when?

Image source, Getty Images
Image caption,

The larger bull shark has its pick of feeding times

The team found that bull sharks hunt mostly in the early morning, while tiger sharks were out more during midday. Afternoons were for sandbar sharks and evenings for blacktips. Both scalloped hammerheads and great hammerheads were most active during the night time.

"It looks like the bigger species - the tiger sharks - have their time and no one interferes with it, so they hunt whenever is best for them," says Georgia Jones at Bournemouth University

Georgia added that "smaller species like the blacktips will work around the times," because they don't want to mess with the tiger sharks and could risk getting eaten themselves!

Image source, Getty Images
Image caption,

Blacktip sharks hunt at times when they can avoid bigger and more dangerous species

All sharks are carnivorous, meaning that they only eat other animals.

There's a wide range of food eaten by sharks and often depends on their size. The animals can eat anything from snails to sea urchins, to crabs, fish and rays, to other sharks, seals and birds.