Santa donned his wetsuit and plunged into a tankful of fish at the weekend.
Staff believe the festive fun has been taking place at Macduff Marine Aquarium for the last 20 years.
Coined Fishmas, the occasion sees the jolly man in his red suit go underwater in one of the main tanks to feed the fish and sea life.
He plunged into the cold water both days this weekend and will be appearing at the Fishmas festivities again on Saturday and Sunday.
Aquarium learning officer Marie Dare said: “This is the 20th year we’ve had diving Santa I think.
“It was a quiet start to Fishmas and less people had turned up than we would have liked but we think that was due to the reindeer parade being at the same time.
“Thankfully Santa will be back again next weekend and there’s so much going on that it will be great.
“We had the 3rd Macduff Brownies singing for us this weekend and the Macduff Rainbows will hae their turn on Saturday.
“All went smoothly with the dives with Santa arriving on time on Saturday despite the weather challenges he and the visitors faced to get here.
“While in the tank Santa feed the fish a variety of foods including mussels, shrimp mackrel and squid.”
In the tank are a wide range of fish which can mostly be found in Scottish seas including halibut, cod, two types of catshark, thornback rays and various others.
As one of the top visitor attractions in the north-east, Macduff Marine Aquarium welcomes around 50,000 visitors per year.
The aquarium is owned and operated by Aberdeenshire Council and aims to promote awareness and enjoyment of local marine life and the environment.
Manager Claire Matthews said: “The best bit for me is that the fish like to nibble on Santa’s beard.
“The fish are very inquisitive and this year there will also be prize draws from within the tank as part of Fishmas.”
There will also be a 12 days of Fishmas trail, crafts and singalongs.
Fishmas will be on again from 11am until 4pm on Saturday and Sunday this week under normal entry prices, with the Santa dive happening at 2pm.