The newest arrivals are two tiny alpacas, born within hours of each other to two different mothers.

And other animals have also been born at the zoo in recent weeks.

Alpacas are members of the llama family and are natives of South America.

The attraction, which lies between Pickering and Malton, has four females in the alpaca herd and two of them, Inca and Jan, were expecting at the same time.

Head keeper Same de Belle said: “To be honest, it was a bit of a race to the finish and we were taking bets among the zoo staff on who would deliver first.”

In the end, it was Inca who went into labour first – eventually giving birth in front of dozens of surprised but delighted visitors at the zoo’s newly-opened South American area.

“The visitors could see a small head and two legs emerging from Inca and they realised at once what was happening, so they dashed to the nearby Boma Cafe,” said Sam. “The staff there alerted us and we went straight to the paddock.”

Mother and daughter are said to be doing well and the new baby has been named Indigo.

Just hours later, in the early hours of the following morning, the arrival of Jan’s new offspring was a much quieter, less public affair.

Sam said: “When we got to work in the morning, there he – or she – was. We haven't been able to determine the sex of the baby yet.”

The alpacas are not the only youngsters proving popular with visitors in the South American section. Henry the Brazilian tapir has been a hit since he was born in January.

Distantly related to both the horse and the rhinoceros, the tiny tapir can be seen most days enjoying a swim in the lake, watched over by his mum, Tiggy.

Elsewhere in the zoo, visitors are cooing over yet more babies, including two new additions to the lemur troop, and some Cameroon sheep.

And the baby boom won’t be confined to the spring – Penny the giraffe, and the growing pride of lions are all expecting offspring a little later in the year.