Large heath butterflies went locally extinct in Manchester 150 years ago but have recently returned to peatlands.
The peat bogs and moss lands of Manchester and Liverpool were home to the country’s biggest colonies of large heath butterflies, known as ‘Manchester Argus’. As this land was drained for agriculture and peat extraction the numbers plummeted.
This rare butterfly has now been found in a 37-hectare restored area of peatland between Wigan and Salford.
Conservations from Lancashire Wildlife Trust recreated the habitats of the species including sphagnum moss, cross-leaved heath and hare’s-tail cotton grass on which the butterflies depend.
Last summer, conservationists collected six female butterflies from a population in Winmarleigh moss near Garstang and took them to Chester Zoo.
The caterpillars spent winter feeding on cotton grass and 45 hand-reared pupae are now being released in a secret, tented site where they will emerge from their pupae.
Heather Prince, who is part of Chester Zoo’s invertebrate team, said: “Breeding and rearing butterflies in an incredibly delicate process that requires a fine balance of conditions at each part of their life cycle.”
She added: “Countless hours have been spent inside our specialised breeding centre nurturing the tiny eggs, rearing the larvae and caring for their host plants as well as monitoring their final pupation period.”
Alan Wright, Communications Manager at the Wildlife Trust for Lancashire, Manchester and North Merseyside says he hopes there will be a good colony here in the next 10 years.
Chester Zoo live-streamed the return of the large heath butterflies on its Facebook page last week, and have regularly been live-streaming a whole range of animals throughout lockdown.