Work to save four of Devon's rarest butterfly species is set to start this winter.
The Devon Fritillary Recovery Project is a two-year land management plan by the Devon Wildlife Trust.
The project aims to help struggling populations of high brown, pearl-bordered, small pearl-bordered and marsh fritillary butterflies.
The charity said numbers had declined dramatically due to changes in farming, loss of habitat and climate change.
It said the high brown fritillary, in particular, had seen its numbers crash by 96% and was now one of the UK's "most threatened species".
Staff and volunteers will now begin work to manage the levels of scrub and gorse at 12 of the trust's nature reserves to ensure the habitats encourage butterfly population growth.
Project officer Jenny Cawson said: "Devon Wildlife Trust's nature reserves offer some of the last homes to our struggling butterflies so it's vital that we work hard to keep them in good condition.
"The launch of our Devon Fritillary Recovery Project signals the start of a huge effort to not only stabilise the populations of these rare species but to restore their numbers.
"The work we'll be able to do during this project will leave a positive legacy which will last for years to come."
The project is receiving support from Natural England's Species Recovery Programme Capital Grant Scheme which focuses on reducing the risk of extinction and promoting the recovery of threatened species.