Staff at Scarborough Sea Life Centre have been counting up the exhibits as part of the attraction’s annual stock take.
Every year, the centre must carry out the “head count” as part of the requirement for its zoo licence.
However, as senior aquarist Todd German explained, it’s not as simple as “two by two”.
He said: “Some tanks are nice and easy, but other can be hard, such as our large ocean tank.
“We have to sometimes do an estimate to the best of our ability. Sometimes we take a photo and count from that.”
Todd said the easiest species to count are the small tank dwellers, such as cowfish and golden finnys. The hardest are the large shoals, such as sailfin tangs and fusiliers.
He said: “Coral can also be tricky. We propagate a lot of them, but in the larger reef tank they do it by themselves.”
The stock take also takes into consideration mortalities and new arrivals.
This year, one of the most significant births has been that of Peso, a baby penguin, who was born in April.
Todd said: “For us to be able to breed them is fantastic - it’s the first baby here in five years.
“He’s done really well. He weighs over six kilos and is one of the fattest penguins in there!”
This year has also seen the birth of a number of pipe fish, seahorses, rays and dogfish.
Everyone is the animal care team is involved in carrying out the stock take, which is submitted in January to Scarborough Council and the Sea Life Centre head office.