A litter of grey wolf pups has been seen in Colorado for the first time in nearly 80 years.
The species was eradicated from the state in the 1940s. Adults known as John and Jane were reintroduced in 2019 and 2020 and they appear to have produced at least three pups.
Voters in Colorado backed an initiative to restore the breed in a referendum last November, intending to establish a viable population by 2023.
"Colorado is now home to our first wolf litter since the 1940s," said the state’s governor, Jared Polis.
"We welcome this historic den and the new wolf family to Colorado. With voter passage last year of the initiative to require re-introduction of the wolf by the end of 2023, these pups will have plenty of potential mates when they grow up to start their own families."
The vote to re-establish the grey wolf in Colorado came a month after it was announced that the species had lost its federal protection under the Endangered Species Act.
However this will not apply in Colorado where capturing or killing a grey wolf will lead to a fine of up to $100,000 (£71,000), a possible jail sentence and the loss of a hunting licence.