SCOTLAND'S economy has become too heavily dependent on economic migrants from Poland, according to a report that warns the country's prosperity could suffer when they return home.

The study by Robert Wright, professor of economics at Strathclyde University, says eastern European workers are less likely to lay down permanent roots here than immigrants from further afield, creating a potentially destabilising problem for the economy.

Those industries most vulnerable to the future withdrawal of the migrant labour force include hospitality, construction, food processing and agriculture.

Wright, an adviser to the government's Office for National Statistics, claims the soaring value of the euro against sterling means Scottish wages are now less attractive as a source of funds to send home to relatives in Poland.

Other prosperous European Union countries, including the Netherlands, have relaxed their labour market laws to welcome Poles since last year, and Germany, their nearest neighbour, will open its borders in 2011.

At the same time, the Polish economy is developing at a rapid rate, generating more and better- paid job opportunities at home.

Of the Poles who came to work in Britain last year, 60% said they intended to stay in the country for less than three months and only 8% said they planned to remain for more than two years.

Wright says that, with Polish immigration already slowing, it is “extremely risky” to rely on it to rebalance Scotland's demographic deficit.

He warns that it could leave the country with an ageing population and an increasing demand for state-funded healthcare, pensions and other services, funded by a falling number of taxpayers.

Instead, he says the UK government should introduce a points-based immigration system that takes Scotland's economic and demographic needs into account.

Poles account for 250 of the 390 employees at Strathaird Salmon, a fish processing firm based in Inverness. Bill MacDonald, its human resources director, said he feared a fall in immigrants would hit its ability to cope with seasonal demand and that it proved more difficult to recruit workers last Christmas than before.

“For the past four years the Poles have really helped us out. Inverness has had such low unemployment that we couldn't have recruited other people locally and their work ethic is good, they're turning up on time and they're diligent.

“We are aware that there is a problem looming, and as we go on and the Polish workforce dries up, it could mean more costs for the company, with more overtime to meet demand. It may be that we have to lower our recruitment standards.”

Meanwhile, hundreds of illegal immigrants - including a suspected murderer and other criminals - are working in care homes in Britain, a leaked Home Office report has disclosed.

In some homes, more than half the employees have entered the country illegally and are now being entrusted with caring for old and vulnerable people.

The immigration intelligence report found that one illegal worker was a murder suspect from the Philippines and others had been involved in the “abuse and mistreatment” of elderly people.

The report, which was produced more than two years ago, warned that the problems were “widespread” and “significant”. But officials say its findings have been ignored.

David Davis, shadow home secretary, said: “The Home Office is turning a blind eye and allowing some of the most vulnerable people to be put in the care of people who by definition cannot have a criminal records check.

“This is putting arbitrary and artificial targets ahead of vulnerable people's welfare. It's an utter disgrace.”

The Home Office said yesterday that it did not comment on leaked documents.

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