She was the second tortoise in a Game and Fish study to have a transmitter affixed to her, which had been providing researchers information about the reclusive reptile's movements since 2010. Fourteen other juvenile tortoises in the program have transmitters.

Anyone with information about this killing can call the department's Operation Game Thief hotline toll-free at (800) 352-0700 or visit www.azgfd.gov/thief and refer to case #14-002388. Callers may be eligible for a reward of up to $1,000.

The pair run the Kentucky Reptile Zoo full-time, a non-profit relying solely on people coming through the gates and the sale of venom.

Kristen added: "Almost any venomous snake is capable of causing severe injury but you are pretty unlikely to die if you get appropriate medical care.

"It's unlikely here as we do everything we can to get appropriate care and have anti-venom on site for everything anti-venom is made for.

"We both believe what we're doing is a good thing - it saves lives."

Acknowledging his decade-long efforts, he was recently given official permission to rescue snakes by the Chief Wildlife Warden with the support of the Conservator of Forest.

“On an average, I rescue five to six snakes in a day. But some days, I get more than 30 calls and it is difficult for me attend to all of them,” said Kiran. In order to address this issue, Kiran has recently registered his society called ‘Snakes Saver Society’ and formed a team with 16 other members, whom he has trained to catch and rescue snakes. “We now want to reach out to city schools and colleges and conduct awareness workshops on snakes and how to be safe,” he said. “There are about 250 species of snakes found in the region, but only a handful of them are venomous,” he said.

"It's a heartbreaking thing when you see them come here, tears in their eyes, and you try to comfort them," said Daniel Marchand, curator at the Phoenix Herpetological Society, a private sanctuary which takes in surrendered reptiles.

But PHS can no longer take in tortoises due to the scope of the current problem.

Releasing them in the wild is not the answer, because one tame tortoise with a virus can kill an entire neighborhood of wild Sonoran Desert tortoises.

Then there's the issue with people finding tortoises in the wild and turning them in to Game and Fish.

"We don't want people turning in baby tortoises," said Burnett. "They're probably wild tortoises, so we want them to leave them in the wild. Obviously, if they're in the middle of the road, move them to the side of the road, but please don't turn in baby tortoises. Let them be in the wild so they don't have to be in captivity."

Mr Britton said fatal attacks had very gradually increased since crocodiles were protected in the 1970s, to an average of one every two years.

"You can get three or four attacks within a short space of time, it doesn't necessarily mean there's suddenly been a dramatic increase in the number of crocodile attacks," he said.

"It just means there's been a dramatic increase in the number of people taking unnecessary risks, or putting themselves in a position that they don't think is necessarily safe, and it's tragic when it happens."

A speed test for the northern pine snake (Pituophis melanoleucus) shows that it takes the snakes 2 minutes to cross a two-lane concrete road. During that time, about 70 cars may pass over a well-used highway to the New Jersey coast. On sand, a trip the same distance would last only 45 seconds, said Dane Ward, a doctoral student in environmental science at Drexel University in Philadelphia.

When a snake moves across a sandy area, it creates sandbanks that it uses to propel itself forward. Concrete does not have enough debris or grip to help with this forward motion, Ward said. "It seems that the snake is having difficulty generating enough lateral thrust to move itself farther," he told Live Science.

To compensate, snakes on concrete roads slither in an "S" motion, which isn't typical for northern pine snakes, Ward said.

A police spokesman said: "It is a highly unusual case but it appears to be just an accident. He prepared the snake himself and was just unlucky.

"There was nothing that could be done to save the man. Only the anti-venom could have helped but this was not given in time. It was just a tragic accident."

The snake was being diced up to be made into snake soup, which is a delicacy in the area and a much sought after dish in high-end restaurants. China has seen a rising demand for snake products, not only in restaurants but also for use in traditional medicine.