Hazel dormice numbers have declined by almost three quarters in the last 20 years, research shows.
The last recorded sighting of a dormouse in the north east was 2006 in Northumberland, according to the Durham Wildlife Trust. Now a research team has cast gloomy predictions for the dormice in the UK - and called for fresh efforts to save the species
Exeter University analysed records from a national dormice monitoring programme run by the People's Trust for Endangered Species (PTES) which collects information on the presence of the tiny mammals in 17,000 nest boxes in 400 woodlands.
Numbers have plummeted 72% between 1993 and 2014, the study published in the journal Mammal Review showed.
The fall amounts to annual declines of 5.8%, it said.
The ongoing decline could mean that hazel dormice are endangered in the UK, the researchers warned.
Cecily Goodwin, lead author of the study, said: "Dormice are declining despite strict protection and widespread efforts to conserve one of Britain's most endearing woodland mammals."
The nocturnal mammals live in woodland, scrub and hedgerows, and are asleep during the day when teams check the nest boxes, enabling them to make a careful count.
They favour new growth trees and shrubs which thrive when taller woodland has been cut down, and the loss of coppicing to manage woods is thought to have contributed to declines.
More fragmented woodlands and loss of hedgerows connecting them up could also play a part.
Study author Professor Robbie Mcdonald said: "Dormice face a range of problems: climate change and habitat loss are likely to be important, but we think that appropriate woodland management could make a big difference."
Nida al Fulaij of the People's Trust for Endangered Species said: "The declines highlighted in this paper are alarming and there is an urgent need to review conservation of hazel dormice to protect this much-loved species".
Efforts to save the dormouse, which has vanished from 17 English counties in the past century, have included 27 re-introductions of captive-bred dormice led by PTES, with 864 dormice released at 22 different sites across 12 counties in England in the past 24 years.