The chances of locating Sydney’s rogue boa constrictor are growing slimmer by the day, according to snake catcher Sean Cade.

Mr Cade has been tasked with finding the reptile, reportedly 2.5 metres long and thicker than a man’s calf.

Skin found earlier this month at the Cascades Estate in Silverdale, in Sydney’s outer west, is the last sign of the snake.

“I’ve had some doozies in my time but this is one of the most unusual ones given it’s a boa of that size – that’s the most alarming thing,” he said.

Mr Cade says while boa constrictors can last a couple of months without food, many things could harm it in the Australian environment.

His main concern was heat, with the mercury hitting 36 degrees on Friday across Sydney, something that would force the snake to lie low until cooler weather and rain.

But Mr Cade said foxes, dogs and even large goannas could cause the snake some grief, while lawnmowers also posed a risk.

There was only a 20 per cent chance of finding it, he said.

“Sometimes you give up on these things and then it just pops up,” he said.

“That’s just the nature of the business unfortunately.”

Mr Cade is almost certain the boa constrictor was illegally bred by a member of the public, rather than being a zoo or safari escapee.

“People do stupid stuff all the time,” he said.

-AAP