Chester Zoo announces birth of ‘exceptionally rare’ twin monkeys

Critically endangered cotton-top tamarin twins have been born at Chester Zoo – boosting international efforts to safeguard the rare species of monkey from extinction.

The zoo’s new duo has arrived to parents Leo and Treat, following a five-month pregnancy.

Weighing just 40g at birth and measuring only 10cm from their heads to the tips of their tails, keepers have compared the twins to the size of “golf balls.” 

Called cotton-top tamarins due to the striking mane of white fur that starts at their forehead and runs over their shoulders, which resembles a fluffy cotton ball, the monkeys are instantly recognisable for their unique appearance. Sadly, this has led to a major decline in numbers as they are often captured for the illegal wildlife trade to be sold as pets.

The miniature monkeys are native to a small area in northern Colombia where only 5% of their original habitat remains intact due to mass logging for the agriculture, paper and timber industries.

As a result, the species is listed as critically endangered on the International Union of Conservation and Nature’s (IUCN) Red List of the world’s most threatened species. It’s estimated that just 2,000 remain in the wild, making them one of the rarest primate species on Earth.

Zoo conservationists are part of a Europe-wide plan to prevent the species from disappearing altogether.

Mike Jordan, Animal and Plant Director at the zoo, said:

“It’s wonderful to see two tiny babies clinging to mum Treat and dad Leo as they leap from tree to tree. When cotton-top tamarins are born they look just like adults, except they’re even teenier – around the size of golf balls!

“Mum and dad have been sharing parental duties and as a result the little ones are both thriving. It’s still early days, so the babies are too tiny for us to confidently determine if each of them is male or female but, in a few months’ time, we’ll know for sure when they grow in confidence and start to branch out and explore the treetops on their own. 

“The arrival of twin cotton-top tamarins is a really important for the species. They’re exceptionally rare as more than 80% of their wild population has been wiped out in the last two decades alone. Only a few years ago, it was reported that around 6,000 of these charismatic monkeys remained in the wild, but right now numbers have hit an all-time low at just 2,000. This severe reduction in their population has meant that our conservation breeding programme, co-ordinated with other major international zoos, is providing an increasingly vital lifeline for the species, as we look to establish a thriving population for the future.”

Cotton-top tamarins use a sophisticated system of facial expressions and more than 38 different vocalisations to communicate defend their territory, call their young and warn the family group of predators.

Chester Zoo is home to eight cotton-top tamarins, including the new babies, and the group can be seen inside its mini-monkeys habitat.

Cotton-top tamarin fact file:

• The two twins were born to mum Treat and dad Leo on 30 June 2024
• Scientific name: Saguinus oedipus
• Habitat: Tropical forests of northwestern Colombia.
• Lifespan: 13 to 16 years in the wild; up to 24 years in zoos.
• Diet: Fruits, insects, and small vertebrates.
• IUCN Status: Critically Endangered.
• Main Threats in the Wild: Habitat destruction due to deforestation, illegal logging, and the illegal pet trade.
• Population in the Wild: Fewer than 6,000 individuals.

Pictured - Two incredibly rare cotton-top tamarins have been born at Chester Zoo.