Is it a shark, is it a chainsaw? It seems to be a bit of both. 

Meet the smalltooth sawfish. Though closely related to sharks, this group of sea-dwellers actually belongs to the ray family. This fish really looks like a shark with a chainsaw on its head. 

And they are huge, sawfish can grow up to 25ft and used to be abundant in the American oceans.

Their saws are impressive weapons which they use for hunting as well as well as some apparent infighting. Many have numerous wounds on their bodies, a sign that they also attack each other with their saws, for reasons which are not quite understood.

Unfortunately, this intriguing species is extremely rare. They are critically endangered but scientists have gained new insights into their habitat, which could now help them survive.

 

In a new publication, researchers say they have discovered the last place in the ocean that this bizarre fish lives.

A team, led by Yannis Papastamatiou of the University of St Andrews in the UK, tagged and tracked over 20 smalltooth sawfish to understand more about their daily habits.

They discovered that the sawfish spend most of their time in a subtropical Florida bay near the coast, the group reports in Global Ecology and Conservation.

It is only by understanding their habitat more that conservationists might be able to prevent this sawfish from going extinct.

“It’s a fascinating animal and one that most people aren’t aware of. We want to promote awareness for these fishes,” says Papastamatiou.

“There’s a big push to learn more about sawfish, the more information we have the better we can inform their management and recovery.”

Although there had been previous sightings in Florida Bay, it was unclear until now whether they were simply passing through or if this was where they lived.

It's now clear that they stay in this bay for several months of the year.

“We painted a picture of who has been where and when. The tags themselves last for years, we aim to get a picture of their movement over longer time frames,” Papastamatiou told BBC Earth

The subtropical environment of Floriday Bay could be critical for their survival. “The results are encouraging, There’s some evidence numbers may be increasing, we have hope of being able to save these animals,” he says.

The next step will be to figure out more about their behaviour in these habitats as well as raising awareness of how endangered they are.

Although fishing sawfish is illegal, the waters they live in tend to be very murky so they may accidentally be caught. But as long as they are released quickly though, these shark-impersonators will be just fine.

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