A man has died after his boat was reportedly struck by a whale and flipped in waters north of Wollongong.
Two men were flung from their 4.8m runabout off Cape Banks at La Perouse in Botany Bay about 6am Saturday.
Water Police responded after receiving reports the boat had been struck by a whale and flipped, NSW Police said in a statement.
One man, aged 61, was pulled from the water unconscious.
"Attempts to revive him were unsuccessful and he was declared deceased," police said.
A second man, aged 53, was treated by paramedics at the scene before being taken to hospital in a stable condition.
Botany's Foreshore Road Boat Ramp has been closed as police continue their inquiries.
The migration of humpback whales near NSW coast takes place between May and November.
Whale-watchers have reported significant activity off Bass Point at Shellharbour in recent days.
Whales have been seen breaching close to shore, while a playful seal has even made an appearance, too, locals say.
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