There are two new animals at the Durrell Wildlife Conservation Trust in Jersey.
Three very rare pied tamarins were born at the wildlife park but one died, despite this the two surviving mammals are thriving.
One of the two surviving animals had to have emergency surgery after it was 'quite seriously injured' at birth.
Pied Tamarins only live around the city of Manuas in Brazil and is thought to be one of the most endangered monkeys.
PIED TAMARIN FACTS
Scientific name: Saguinus bicolor
Animal type: Mammal
Location: A tiny patch of forest in and around the city of Manaus in Brazil
Conservation status: critically endangered
The two surviving tamarins have not been named yet and they were rejected at birth by their mother, Eulalia.
The new arrivals are being looked after by foster parents Flash and Elsa who keepers say have "proved to be wonderful parents in the past".
The injured animal was just 45g and 8cm long when Durrell vet Juliet Smithyman had to carry out the emergency surgery.
After they were born and the surgery the two tamarins were fed formula milk every two hours around the clock by keepers.
Commenting on the new arrivals Mammal keeper Jenna Pick said "The birth of these two infants is fantastic; it represents a great boost to the health of the captive population."
In the wild, the species is becoming increasingly threatened as it is only found in and around the city of Manaus in Brazil.
Over the last ten years the city has expanded greatly impacting on the forest habitat of the Pied Tamarins.
Deputy Head of Mammals at Durrell, Dominic Wormell, said they were working here and in the Amazon to preserve the animal.
He said: "Along with its conservation breeding programme Durrell is supporting those working out in the field to conserve this fantastic little monkey of the Amazon."
Both tamarins are now doing well.
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