A monster reticulated python dubbed ‘‘Atomic Betty’’ has weighed in at a svelte 137kg, after her keepers at the Australian Reptile Park in Gosford decided she was getting a little too rotund.

Betty had hit 135kg last year, prompting park staff to put her on a limited diet.

Reticulated pythons are the longest species of snake in the world and Betty is believed to be the biggest in Australia.

The 6.5 metre snake had staff in hiss-terics as they tried to bag her for her annual weigh in earlier today.

It took six reptile keepers half an hour to bag the park’s biggest catch and potential man-eater.

When they finally got the snake to the scales, it was revealed she had put only 2kg since the previous year.

Tim Faulkner, the park’s operations manager, said it was no mean feat to get Betty, who has the ability to crush a person to death and swallow them whole, out of her glassed enclosure.

‘‘The scary thing is that she has the ability to crush us,’’ he said.

‘‘You’ve got about a second to grab (her head) because as we go down they’ve got extremely good vision and she is going to strike.’’

Mr Faulkner said Betty’s favourite food was goat.

‘‘She didn’t grow by a lot and that’s because we actually stopped her from consuming as much food,’’ he said.

‘‘This year she only had about three or four goats as opposed to maybe 10 because she was getting a little bit too round rather than getting longer.’’

Betty usually swallows a goat in about an hour though it takes up to a week to digest.

She was imported from the US in 2001 and is expected to grow another metre in the next seven years.

The reticulated python is usually found in southeast Asia.

The constrictor is non-venomous but is a man-eater and strong enough to swallow a human whole.