The man had been returning from a fishing trip at North Head Sanctuary in Manly when he lost his footing and fell about three metres.

He suffered leg injuries, including a broken ankle, and was flown to hospital on Sunday afternoon once he was winched to safety by an ambulance helicopter.

The man “simply lost his footing” when he fell on the north edge of the sanctuary, a Westpac Life Saver Rescue Helicopter spokesman said.

“He was leaving the rock fishing site and climbing up the face of the cliff,” CEO of Westpac helicopter Stephen Leahy said.

“[Rock fishermen] know how to get down. Sometimes it’s more tricky getting back up, especially when you have a bucket or two of fish to take with you.”

Mr Leahy said rock fishermen had often been warned about wearing life jackets but they should also assess risks of getting to and from “amazing, inaccessible” fishing locations.