How Hummocky's (Mount Chappell Island) super-sized tiger snakes outgrew their mainland counterparts
But for Pakana ranger Grahame Stonehouse, those snakes are just another part of his day. Mr Stonehouse is one of two people living on the island, which is an Indigenous Protected Area.
For 11 years, he has split his time between Hummocky and mainland Tasmania.
The ranger describes the island's snakes as "twice as big" as their relatives in other parts of the country.
It's a conservative description, in comparison to local legends about highly venomous, barking snakes; and "fair dinkum" stories about visitors retreating, after the sudden appearance of four or five "big buggers".
Herpetologist Simon Fearn is also familiar with the island's tiger snakes and his work sorts the myths from the truth.
The scientist has studied the reptiles for years, and was even bitten by one on a visit to the island in 1991.
Welcome to 'Snake Alley'
By early afternoon, Mr Stonehouse has already seen three large tiger snakes, but he's not bothered by their presence.
"They don't want to use their venom on you, they want to use it on a feed," Mr Stonehouse says.
"I've got a lot of respect for them."
After less than 10 minutes of searching, he spots a snake.
But it quickly moves out of sight, into a short-tailed shearwater bird burrow.
Commonly known as mutton birds, short-tailed shearwaters make burrows that provide both shelter and food for the snakes, which gorge on the birds' chicks.
Mr Stonehouse says stories about the number and size of snakes on Hummocky have "gotten out of hand", but the reptiles are plentiful and larger in size.
"They're jet black, you don't see no stripes on them," Mr Stonehouse says.
Marooned snakes adapt to island, feasting once a year
Hummocky tiger snakes may not be as large as legend would have it, but herpetologist Simon Fearn says they are consistently longer and heavier, with bigger heads.
Mr Fearn is part of the Natural Sciences team at the Queen Victoria Museum and Art Gallery in Launceston.
"Lots of tiger snake populations were stranded on islands when the sea level rose after the last ice age," Mr Fearn explains.
"Really tiny islands like Chappell, any of the animals stranded on there would have died out quite quickly, so the tiger snakes would be losing types of prey."
Mutton bird chicks are available to the snakes for about five weeks of the year, after which they become too large to eat.
The smaller the snake's head, the less time it has to consume the rapidly growing chicks.
"There's about 20,000 baby snakes born on Chappell Island every year and less than 1 per cent reach adulthood," Mr Fearn says.
"It's only the biggest, fastest-growing baby snakes that can jump the gap from skinks to their first mutton bird chicks."
Through survival of the fittest, the island's tiger snakes have evolved over thousands of years to have larger heads.
The snakes are at their heaviest in February, after gorging on mutton bird chicks, then slowly reduce in weight and activity until the next mutton bird hatching season.
Once the chicks are too large to eat, the snakes curl up in the burrows and use the living chicks as a heat source.
"For the rest of the year they burn off fat, that's why Chappell Island is relatively unique … because there's no other food for the snakes," Mr Fearn says.
Mr Fearn points to naturalist Eric Worrell, who visited Hummocky in the 1950s to collect hundreds of snakes.
"He used to go there and pillage the island for snakes to milk for venom," Mr Fearn says.
"He wrote lots of popular articles about it and made the island famous and the size of its snakes famous.
"The problem is … there are probably 40 islands in Bass Strait with tiger snake populations and none of the others have been studied much – there are probably other islands with snakes just as big."
Are they more venomous?
"People confuse toxicity, how potent the venom is, and the quantity of venom," Mr Fearn says.
"Chappell Island tiger snakes are amongst the least venomous tiger snakes, but because they're so big and have such big heads, they inject a lot more venom."
The herpetologist has direct experience, after suffering a snake bite on the second last day of a six-week visit in 1991.
Connecting with culture by working to restore country
For Mr Stonehouse, the island is a place of calm that has helped him reconnect with his culture and country, after being removed from his family as a child of the Stolen Generations and taken away from Tasmania.
"I'm part of the Stolen Generation — 15 kids mum had, I was the only one in the family taken away from Tasmania," Mr Stonehouse says.
When Mr Stonehouse eventually returned to Tasmania after living in Queensland, he got to know his Tasmanian family and sought opportunities to reconnect with country too, through his work on the land.
"The whole island here at one point was covered in boxthorn, we got it to 25 per cent left," Mr Stonehouse says.
"I've always wanted to get in touch with the land."
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