A three-month study has found that the number of red squirrels grew by 7% last year in the north of England. It’s the first time in 140 years that the population has increased.

The study, carried out by volunteers for wildlife group Red Squirrels Northern England (RSNE), also saw the first red squirrels in Ambleside and Rydal in Cumbria for a decade and found that the number of grey squirrels carrying pox had fallen.

The Prince of Wales told the Daily Telegraph this was “the most encouraging news we have received for many years”. The patron of the Red Squirrel Survival Trust said: “I can only offer my congratulations to all concerned, as I know full well how much effort has gone into this promising result.”

“I do hope that we begin to hear similar positive conservation stories elsewhere around the country as more people join the fight to protect our precious native red squirrels.”

The RSNE said that preserving habitats and conservation projects have helped the species to recover.

The news will strengthen the concerns over plans already approved to fell trees in a forest in Anglesey that is just one of three red squirrel habitats in Wales.

The group used visual counts and remote cameras, as well as sticky pads to trap red squirrel hairs, in order to monitor the population of red squirrels.