It's a census with a difference - scuba suits and aqualungs alongside the clipboards and pencils.
Yes, staff at Bristol Zoo are conducting their annual census. There are more than 400 species at the zoo and keepers say the population is growing because of successful breeding programmes. But counting the animals isn't always easy. With fish there is no avoiding it -you have to get wet.
Big tanks you can see we do get in those - it's a lot easier to count the animals that way because we can look in all the nooks and crannies.
We need to make sure our records tie up with what we've actually got on our displays. It's very difficult with small animals - we classify them as big groups.
We've got a lot of small fish in big tanks so it's more to do with the breeding. We have a lot of fry coming through that we might miss.
Keepers at Bristol Zoo will begin their annual census today. Over 400 species need to be counted.
The animal stock take is done at the start of every year and gives keepers the opportunity to check their computer records are up to date. Staff say 2014 has been a successful year for breeding - including the birth of pygmy hippo Winnie.
Penguins are all the rage this Christmas, thanks to THAT TV advert but Bristol Zoo is drawing attention to the plight of penguins in Africa, which it warns are at risk of extinction.
The population of African penguins fell 70% between 2001 and 2013 and is continuing to decline.
Every winter, hundreds of African penguin chicks, who have been abandoned by their parents foraging for food, are rescued by a rehabilitation centre in South Africa, in a project led by the Bristol Zoological Society.
This year. the youngsters are coming into the centre in their hundreds from the colonies. The rehabilitation centre is already helping to care for 430 and this number continues to grow faster than expected.
With the price of fish soaring, an extra £20,000 is needed before Christmas to enable food and care to be provided for all the chicks.
There are less than 18,000 breeding pairs left in the wild in South Africa. African penguins are an endangered species so every individual possible needs to be saved to increase numbers in the wild.
Unless conservation organisations intervene, these chicks will starve to death. As African penguin populations are currently facing a crisis due to a diminished food supply near their nesting colonies, there is a substantial risk that this species could eventually become extinct without action.
To find out more about the plight of the penguins, click here.
It's been a record breaking year for bird keepers at Bristol Zoo. Huge numbers of chicks including some endangered species have hatched over the last few months. Among the new arrivals are 10 baby flamingoes - some of which had to be hand reared.
Rob Rouse, keeper at Bristol Zoo, explains what the future holds for Winnie the baby pygmy hippo.
Winnie the pygmy hippo was born at Bristol Zoo Gardens in February and has since enjoyed romping around her enclosure with her father Nato and mother Sirana - who is ferociously protective. Today she was allowed outside for the first time.
Fewer than 2,000 pygmy hippos survive in the wild.
Staff at Bristol zoo are taking extra care of a giant tortoise with a nasal infection. Helen, as she's known, had to be taken to the vets after attempts to treat her on site didn't work. It wasn't easy as Hannah Gamlin reports.
A giant Tortoise at Bristol Zoo has been feeling a bit under the weather. That's because she's been diagnosed with a cold!
Helen, who weighs 14 stone was checked into the Zoo's clinic after keepers found that she had the sniffles.
It took four men to lift the 32 year old Tortoise who's been at the Zoo for 11 years.
She was given a nasal flush and is now on the mend
Helen is an Aldabran giant tortoise – a species classified as ‘vulnerable’. Giant tortoises can live up to 150 years old.
Bristol Zoo has unveiled its latest arrival - a baby pygmy hippo. Winnie is three weeks old and never far away from her mother Sirana, who is very protective of her.
Winnie's birth is a big success for the zoo's captive breeding programme - it's thought less than 2,000 of the animals survive in the wild.