A pilot study conducted at the University of Missouri showed that the synthetic chemical bisphenol A — or BPA, which is known to mimic estrogen and disrupt hormone levels in animals — can alter a turtle’s reproductive system after exposure in the egg. Turtles are perfect creatures for this type of study, because their sex is determined by the temperature of the environment during their development in the egg.

“Cool dudes or hot babes,” explained Sharon Deem, director of the St. Louis Zoo’s Institute for Conservation Medicine and a lead investigator on the study.

The researchers dropped a liquid form of the chemical onto hundreds of eggs that were incubated at cooler temperatures required to produce male turtles. A few months after they hatched, the turtles’ sex organs were removed and studied. The male turtles had developed gonads that were closer to ovaries than testicles.

The Jamaican iguana is listed as a critically endangered species, but it has been saved from extinction. However, this triumph of the conservation movement is now threatened by the plan to turn the Goat Islands into a $1.5-billion economic zone, transshipment port and logistics hub.

The official name for the project is the Portland Bight Economic Zone and Transshipment Port, and foreign journalists seem to be converts to the campaign against it. The Guardian newspaper in London recently published a portfolio of beautiful photographs of the lizard by the prize-winning photographer Robin Moore.

But it is not just the lizard that is threatened. The livelihood and way of life of fishing communities in and around the Goat Islands would disappear. And the flattening of the Goat Islands, as well as the dredging involved, would threaten 50 species of plant life found only in Jamaica, including 17 that are endangered.

Known as The Snake Lady, Wiley earned national recognition for her collection of reptiles and venomous snakes. Some of her snakes were featured in films such as “The Jungle Book” and “Cobra Woman.” Wiley herself appeared as a snake charmer in the film “Moon Over Burma,” starring Dorothy Lamour.

Born in Chanute, Kan., in 1883, Wiley, who has been described as headstrong in many biographical accounts, attended the University of Kansas at a time when very few women sought out a higher education.

She began collecting and observing rattlesnakes while doing fieldwork in the Southwest, and within a few years she became the first person to successfully breed rattlesnakes in captivity.

Helen, a 90kg (14 stone) tortoise, was given a health check after keepers noticed her unusual breathing.

Staff vet Richard Saunders said: "The whistling, raspy breathing in her nose could be heard from several feet away, so we took samples under anaesthetic."

The 32-year-old tortoise, described as a "good patient" by Mr Saunders, is currently on a course of antibiotics.

The incident, in 2009, naturally drew headlines. While there had always been turtles in the Jamaica Bay Wildlife Refuge, just south of Kennedy Airport, their occasional presence on the airport’s grounds did not normally cause a stir.

But on that July day five years ago, Russell Burke, the chairman of the biology department at Hofstra University, said, “Something made a huge number of turtles come up to Runway 4L.”

Two years later, it happened a second time. And on Thursday, a group of turtles appeared on Runway 4L yet again, despite recent steps aimed at keeping them away.

For Dr. Burke, who has long studied the terrapins that live in the wildlife refuge, the reptiles’ repeated forays onto the tarmac are the subject of serious study. Shortly after the first invasion, the Port Authority of New York and New Jersey enlisted him to help it come to a better understanding of the turtles and their mysterious ways. As part of that effort, he works closely with the Port Authority’s chief wildlife biologist, Laura Francoeur, who described the turtle takeovers as among the more vexing challenges confronting her unit.

This staggering increase means the reptiles, which are indigenous to Grand Cayman, can now be moved off the critically endangered list.

“Previously they were listed by the International Union for the Conservation of Nature as being critically endangered, which is actually only one step away for being extinct in the wild,” said Mr Watler. He went on to tell Cayman 27 that, “the fact is that this is an upgrade, it sounds kind of counter intuitive to say its a good thing that they are only on the endangered list but it really is much better than being critically endangered.”

LSTM's Dr Nicholas Casewell, first author and NERC Research Fellow, said: "Our work shows that venom variation observed between related snake species is the result of a complex interaction between a variety of genetic and postgenomic factors acting on toxin genes. This can involve different genes housed in the genome being turned on or off in different snakes at different stages of venom toxin production. Ultimately, the resulting venom variation results in significant differences in venom-induced pathology and lethality and can undermine the efficacy of antivenom therapies used to treat human snakebite victims."

It's a specialized culvert built in Germany, which has small holes at roadway level to allow sunlight to get into the tunnel.

The location was picked after the MN Herpetological Society documented a large number of turtle crossings which were deemed hazardous to both turtles and motorists, who were stopping on the two-lane highway to avoid hitting them.

The $50,000 price is paid for with a $10,000 grant from the University of Minnesota, a $37,000 grant from the DNR's Legacy funding, and $3,000 from the Herpetological Society.

Stephen Loman and William Sargent know more than most just how closely we live with snakes. Although the pair balk at the term snake hunter, they have been rescuing, photographing and releasing snakes in the wild in Hong Kong for decades.Stephen Loman and William Sargent

In that time, Loman, a finance professional, and Sargent, a race organiser, have caught and released more than 1,000 snakes and suffered hundreds of bites.

Even so, both argue - and experts agree - that the fear of snakes is often misplaced. "Snakes get a bad reputation," says Sargent. "A lot of people don't know much about snakes. That fear or ignorance leads to killing snakes for no real reason."

In his experience, it is humans who are a menace to snakes, not the other way around. According to the Hospital Authority there hasn't been any death attributed to a snake bite in more than 20 years although Hong Kong has some particularly venomous species such as the banded krait, Chinese cobra, coral snake and the red-necked keelback.

Dying from a snake bite, even from the most poisonous species, is "very rare" in Hong Kong for several reasons, Lau explains. The city is small, has good infrastructure, and a high standard of medical care. No matter where someone is bitten in Hong Kong, they are never more than an hour away from hospital, and all major hospitals carry antivenom.