Open season has been declared on ring-necked parakeets — the vibrant green squawking birds seen across parts of southern England.

The parakeets are considered by government nature advisers as great a pest as the grey squirrel, and from January 1 anyone troubled by the birds has permission to kill them with a shotgun or rifle, or trap them in a cage or net. Their eggs and nests may also be destroyed.

The shrill call of the birds heard across parks and domestic gardens is, however, insufficient reason to kill them. Farmers, homeowners and councils can only kill the birds if they have damaged wildlife habitats, crops, timber or fisheries, or to prevent spread of disease.

Under revised rules from Natural England, the Government’s wildlife advice body, the parakeet has joined the magpie, crow and rook on a general licence, which means they can be killed without special permission.

Ring-necked parakeets, with vibrant plumage and scarlet beaks, were first reported breeding in the wild in Britain 40 years ago.

Many are thought to have escaped from private aviaries, while others were said to have been released by sailors returning from overseas. Some are even thought to have escaped from Shepperton film studios in 1951, during the making of The African Queen — when exotic birds were used in jungle scenes.

Today there are an estimated 4,700 breeding pairs in Britain. The birds are blamed for damaging trees and stealing nesting holes used by woodpeckers. Other birds added to the general licence are monk parakeets from South America, Canada geese and Egyptian geese, all of which pose some threat to wildlife, crops, public safety or public health, according to Natural England.

The body insisted that the change is not “a call to arms” against the birds. A spokesman said: “You have got to have good reason to get rid of them, and you have to demonstrate the damage they cause. It doesn’t mean anyone can take pot shots at parakeets in parks. The dispatch can only be done by the land owner or someone authorised.”

Helen Phillips, chief executive of Natural England, said: “Non-native species are a threat to global biodiversity, and it is important that licences can operate as an effective tool to tackle the problem.”

The conservation body also announced that two native species, the herring gull and greater black-backed gull, have been removed from the list, and will require specific licences.

Some farmers and landowners however are concerned they will no longer be able to shoot greater black-backed gulls, which they say threaten poultry and young lambs. They claim it takes too long to fill in a form and apply for special authority.

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