Tiny rare dormice underwent a health check as the ZSL London Zoo prepares to release them into the wild in an effort to reintroduce the species once common across England and Wales.

Each British hazel dormouse, weighing 20g, had a 10-minute appointment in which they were placed under a miniature dormice-sized dose of general anaesthetic while they underwent health checks and a tiny microchip was placed under their skin for easy identification in post-release monitoring.

The release is part of a long-term project to rebuild populations and restore the range of the native species.

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