Images show fish avoiding the jaws of a shark in their midst


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They are one of the most feared animals on the planet.

Now fascinating images reveal how fish make a collective effort to stay out of the way of sharks.

The striking photographs show a shoal of fish making way for the blacktip shark swimming in the shallow waters of Heron Island in Queensland, Australia.

Incredible images show a shoal of fish making way for a blacktip shark (pictured), perhaps proving that they are instinctively frightened of it

Incredible images show a shoal of fish making way for a blacktip shark (pictured), perhaps proving that they are instinctively frightened of it

It is thought that the reef shark was not interested in catching a meal, but the fish naturally keep their distance, creating circles of clear water around the predator. 

Fish are thought to gain many benefits from shoaling behaviour, such as keeping safe from predators as well as boosting their chances of feeding and finding a mate.

It's known that shoals of fish can change shapes and directions in seconds - as if they are thinking as one - and in these images, the fish manage to keep a pocket of clear water between themselves and the shark, even the pocket does change shape.

Software engineer Scott Carr was looking for a picturesque spot to have photos taken before his wedding when he came across the shoal of fish trying to avoid the shark.

Luckily, the 32-year-old was carrying his camera to snap the scene.

'There were four blacktip reef sharks circling the area and there was one other type of shark - a lemon shark,' he said.

'We walked along the jetty looking down at a large school of fish just beneath the jetty.

The photos show a shark swimming in the shallow waters of Heron Island in Queensland, Australia, where they are guaranteed a clear path because 'terrified' fish move out of their way

The photos show a shark swimming in the shallow waters of Heron Island in Queensland, Australia, where they are guaranteed a clear path because 'terrified' fish move out of their way

THE BENEFITS OF BEING IN A SHOAL

It's thought that shoals may be an effective means for the majority of fish within them to escape predators' jaws, because they confuse larger creatures.

The 'predator confusion effect' is based on the idea that it becomes difficult for predators to pick out individual prey from groups because similar-looking fish create a sensory overload for predators.

Fin movements made by a shoal seem to overlap to mimic waves created by a larger animal, perhaps to dissuade a predator from attacking.

The fact that there are many fish in a shoal means they have many eyes to scan an area for predators and keep out of the way.

The look-out is shared between individuals to let the group feed safely and swim away from predators as a group.

'We noticed a number of reef sharks patrolling the area near the jetty and as we watched the reef sharks slowly moved into the school of fish, with the fish retreating away from the immediate area around the shark.

'This progressed for about 15 to 20 minutes and a lemon shark joined in on the action late in the piece.

'It seems like the fish are well aware of the threat and are trying to keep a safer distance from it. They want to avoid being eaten!'

He noted that the sharks were 'remarkably calm' when moving though the fish.

'It was certainly not what I would describe as a feeding frenzy at the time.

'There was an occasional swift manoeuvre to attempt to catch a fish and the sharks were successful in some of these attempts.

He added: 'Watching the continuous parting of the school of fish as each shark moved through the mass of fish was absolutely spectacular!' 

Whether fish feel fear (illustrated by a still from the film Finding Nemo' is a slippery question for scientists. Some studies claim that fish feel pain, but shoaling behaviour's thought to be purely instinctive

Whether fish feel fear (illustrated by a still from the film Finding Nemo' is a slippery question for scientists. Some studies claim that fish feel pain, but shoaling behaviour's thought to be purely instinctive

Software engineer Scott Carr was looking for a picturesque spot to have photos taken before his wedding when he came across the shoal of fish trying to avoid the sharks
Software engineer Scott Carr was looking for a picturesque spot to have photos taken before his wedding when he came across the shoal of fish trying to avoid the sharks

Software engineer Scott Carr was looking for a picturesque spot to have photos taken before his wedding when he came across the shoal of fish trying to avoid the sharks (pictured left and right) near a jetty

Whether fish have emotions, is a slippery question for scientists, whose studies have shown that they can feel pain in an abstract way, as well as other emotions.

Whether fish feel fear, or simply act instinctively, they swim in large shoals that offer individuals more protection from predators than going it alone.

Shifts in the shape of the shoal is thought to be driven by feeding, travelling and avoiding predators.

It's thought that shoals may be an effective means for the majority of fish within them to escape predators' jaws, because they confuse larger creatures.

Proposed in 1978, the 'predator confusion effect' is based on the idea that it becomes difficult for predators to pick out individual prey from groups because the many moving targets create a sensory overload of the predator's visual channel – a theory that's been proved in the wild and in computer simulations.

There is also a theory that fin movements made by a shoal overlap to mimic waves created by a larger animal, perhaps to dissuade a predator from attacking. 

It's possible that if one shark was found among the shoal (pictured) and others around it, they could act collectively to corral a shoal for a quick meal.

It's possible that if one shark was found among the shoal (pictured) and others around it, they could act collectively to corral a shoal for a quick meal.

The fact that there are many fish in a shoal means they have many eyes to scan an area for predators and keep out of the way.

The look-out is shared between individuals to let the group feed safely and swim away from predators as a group.

It's possible that if one shark was found among the shoal and others around it, they could act collectively to corral a shoal.

This behaviour isn't common in sharks, but dolphins have been shown to surround and herd fish as a group, while individuals take it in turns to swim through the shoal, eating unlucky members.

Corralling is a method where fish are chased to shallow water where they are more easily captured and Atlantic bottlenose dolphins even chase fish onto mud banks for an easy meal.

In the shark world, Thresher sharks use their long tails to stun shoaling fish.

Before striking they confine lots of fish in a small space by swimming round them, and then splash then strike them with the upper lobe of the tail to stun them.



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