Scotland’s islands have the highest proportion of co-operatives of any part of the UK thanks to a long tradition of self-reliance, a survey has found.

The study by Co-operatives UK, the sector’s development body, said its survey of co-ops by local authority area found the Western Isles and Orkney topped the table with 8.16 and 5.91 co-ops respectively per 10,000 people. Shetland came in third, with 5.63. Eden in Cumbria came in joint fourth, with 4.55, followed by nearby Allerdale with 3.6.

The Scottish sector’s businesses are generally small, often community shops which provide the only stores in scarcely populated island communities. There are also credit unions, community energy companies and fishing co-ops.

The findings have been published as part of Co-operatives UK’s annual economic survey. It put its total turnover UK-wide at £37.7bn for 2018-19, a little over 1% higher than last year’s figure of £37.6bn and 2.75% higher than the £36.3bn in 2016-17.

The study confirmed that the John Lewis Partnership, the employee-owned group which includes Waitrose food stores, was the UK’s largest co-op with a turnover of £10.3bn; the Co-op itself narrowly behind on £10.2bn. Arla, the Denmark-based diary co-op, came third with a turnover of £2.6bn.

Excluding turnover, the data shows a slight decline in the sector’s size overall. The UK had 7,215 co-ops employing more than 233,000 people in the last financial year, compared with 7,226 employing nearly 235,000 a year earlier.

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The report highlighted the Papay Community Co-operative, which runs the only shop and hostel on Papa Westray. The Orkney island has a resident population of about 85 people but is popular with island-hoppers on holiday. The business is close to Papa Westray’s airport, famous as a departure point for the world’s shortest scheduled service, a two-minute, 1.7-mile (2.8km) flight to nearby Westray.

Tim Dodman, the co-op’s secretary, said the business had an annual turnover of about £250,000 and employed four people, with some part-time help during busy periods. It also runs the school bus and local tours.

It was founded in 1980 after the only shop closed and no one could be found to run a new one single-handed. “The co-op ethos is very important,” Dodman said. “This is a small island and pretty remote. It’s much better to work cooperatively than have one individual in control of a lifeline service.”