geese are wreaking havoc on a group of Scottish islands, causing serious damage to the livelihoods of local crofters.

The birds are causing devastation on the Uists in the Outer Hebrides by ruining cereal crops and grass with their grazing and fouling.

Now the Scottish Crofting Federation (SCF) has called for an end to the ban on shooting greylag geese throughout the year to combat the problem.

SCF chairman Derek Flyn, who is also a lawyer and an expert on crofting law, said: "Crops of cereal and grass are being ruined by grazing and fouling by geese. A crofter will wait on tenterhooks for the crop to ripen, balancing this against the risk of the geese coming. If he is unlucky, just when the crop is capable of being harvested they move in and completely destroy his field in hours."

He added the greylag goose was once considered rare in Britain. In 1986 it was estimated there were only around 700 to 800 breeding pairs in the UK.

But the Uists – which include North and South Uist along with Benbecula – are a year-round home to more than 10,000 greylag geese and that population is growing. Crofters say they can only tolerate up to 4000 geese.

Mr Flyn added: "Crofters are told they can shoot marauding deer on their crofts but not geese, except at certain times of the year and at the will of the landlord who has the shooting rights and dictates whether crofters can shoot or not."

He said the SCF had two objectives: to get funding to protect crops; and to change the law regarding geese control and meat sales.

He added: "There is a catastrophe unfolding. Crofters and their families are now the endangered ones. Wild goose should become part of the Uist diet – it is local food – but it should also be a commercial opportunity."

Rebecca Cotton, Project Manager of Machair Life+, a European-funded environmental programme that runs a crop-protection scheme, said: "Geese are the single biggest threat to island crofting. We talk about the need to retain young people as the most important contribution to the sustainability of the Western Isles, but in crofting terms there will be nothing left for the young people unless we do something about the goose problem now."

David Maclennan, Scottish Natural Heritage's area manager for Argyll and the Outer Hebrides, said crofters' concerns were recognised. He added SNH was working with other bodies to find a workable solution.

He said tests were being carried out to see whether local populations of geese could be managed effectively.

Mr Maclennan added: "We're exploring a number of angles – including deploying marksmen, co-ordinating volunteer input, using decoys, licensing, changes in legislation, and demonstrating the value of goose meat as high-quality local produce."