Researchers tracking mako sharks along the Atlantic seaboard have more to contend with than just nature.

Some of the sharks have ended up in the lines of commercial fishermen, and while it’s not illegal to catch the sharks, it is expensive and frustrating for the researchers.

American researcher Anthony Mendillo is helping scientists from Florida catch and tag the sharks.

“We have fish that were tagged in the Caribbean and made it all the way up here to Nova Scotia,” he says.

Mendillo says that, in just two years, four of 13 tagged makos have been caught and killed by commercial fishermen, and that losing the sharks and the equipment can mean major setbacks for scientists.

“It would be wonderful if they were to just take a photograph and let the animal go because it is making a major contribution to us,” says Mahmood Shivji of the Guy Harvey Institute.

Shark SOSF4 was tagged in Maryland and made it all the way to the Grand Banks of Newfoundland. The tracker then shows the mako made a beeline for the shore, except the shark and its $2,000 satellite transmitter were left on the back of a boat.

“We can see pretty much where the boat is tied up, where the tag is,” says Mendillo.

Even though SOSF4 was dead, the tag’s battery wasn’t, and can be used on another shark.

“I asked the people who I was here with, ‘who would be fishing out of this harbour and who do you know who would be doing this?’” says Mendillo.

The question was soon answered, with the help of Capt. Camille Jacquard and Facebook.

“Within about 12 minutes, we had the search narrowed down to two people and within 15 minutes the two were eliminated into one,” says Jacquard.

The fisherman has agreed to return the valuable tag and he will receive a $100 reward for doing so. The equipment will then be redeployed.

With files from CTV Atlantic's Kelland Sundahl