Two endangered monitor lizards have hatched at Bristol Zoo Gardens - making it the first zoo in the UK to have successfully bred the species.

The blue-spotted tree monitor lizards are classified as endangered in the wild and there are only 70 of them in captivity across the world.

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At just 13 grams each, the baby lizards are mostly tail. The young reptiles are 27cm long and two thirds of that is their tail! By the time they are fully grown, they will measure 1.1 metres.

The new arrivals hatched in the reptile house at Bristol Zoo, emerging from their 5cm long eggs which have been in incubation for the past five months.

Staff at the zoo have been closely monitoring the eggs, keeping them at a constant 31°C and looking after the lizards' parents too.

The successful hatchings are a UK first. Credit: Bristol Zoo Gardens

Bristol Zoo's senior reptile keeper, Adam Davis, said the breeding programme is "vital" to the blue-spotted tree monitor lizards' survival.

The programme is vital to their survival, so every single one of them is extremely important.

Adam Davis, senior reptile keeper at Bristol Zoo
The lizards are at risk in the wild as many are caught and sold in the international pet trade. Credit: Bristol Zoo Gardens

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Staff are yet to find out if the new arrivals are male or female - it will be 18 months until the keepers can be certain.

Curator of reptiles and amphibians, Tim Skelton, said the hatchings were "a real first" in the UK.

The blue-spotted tree monitor was first discovered in 2001 on an island off the coast of Indonesia, but was already classed as endangered by 2017.

The lizard is largely at risk due to the international pet trade.

Read more: Bristol Zoo Gardens welcomes new Asiatic lion.