A large rescue operation was launched to find Ivan Duychau after he failed to return to a dive boat in the Pentland Firth on Wednesday evening.
Three lifeboats and two helicopters spent hours searching for the missing diver before he was discovered by a Russian sail training vessel two miles east of Duncansby at 3.15am on Thursday morning.
The crew of the boat, the Yunyi Baltiets, told Shetland Coastguard they had a doctor on board and that the diver was alive and not in immediate danger.
Mr Duychau was later transferred to the RNLI Thurso lifeboat before being taken to Wick Hospital on the Scottish mainland, where he is said to be “conscious and in a reasonable condition”.
Shetland Coastguard said the overnight search had involved RNLI lifeboats from Thurso, Longhope and Stromness as well as two rescue helicopters.
“During search operations at sea, it’s incredibly challenging to spot a head in the water especially at night,” said Gary Harris, who was co-ordinating the incident in Shetland Coastguard Operations Centre.
He added that Mr Duychau was “very fortunate” to have be spotted by the crew on the sail training vessel and was in reasonable health considering how long he had been in the water.
The incident follows the incredible rescue of Mr Bryce, 22, who was plucked from the North Channel 13 miles from Northern Ireland by a helicopter on Monday evening.
The surfer had been reported missing by his family after failing to return from a Sunday morning surf off Scotland’s Argyll coast.
Mr Bryce is believed to have survived for so long as he was wearing a wetsuit and had managed to stay with his surfboard, which kept him out of the water.
He is now recovering from the effects of hypothermia at a hospital in Belfast, where he said: “I can’t thank those enough who rescued and cared for me – they are all heroes.”
Last month another diver was rescued from the sea off Orkney by an offshore support vessel after failing to return to his boat on time.
The man had been diving for scallops between the islands of Stronsay and Eday on 16 April and was transferred to hospital to recover after being found.
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