Northern Europeans. Some residents expected an increase in tourism due to the filming of Mamma Mia! on the island in September 2007. Agriculture, once a staple of the local economy, is in decline. Plum and almond orchards exist but are less extensive than in the past. Wine production from local grapes is minimal ever since the phylloxera blight of the 1940s destroyed the vineyards. Though there is local small scale wine production using local grapes, most wine produced on the island is for home use and much is pressed from grapes imported from Thessaly. Herding of domestic goats and domestic sheep continues and a local feta type cheese (katiki) is produced from these stocks. Beekeeping and honey production have increased in recent years. Skopelos supports a small fishing fleet which fishes local waters. The island once had a vital wooden shipbuilding industry and contributed many ships to the War of Greek Independence (1821–1831). Shipbuilding began to decline after the introduction of steamships. The Encyclopædia Britannica Eleventh Edition (1911) stated "Almost every householder in both islands (Skopelos and Skiathos) is the owner, joint owner or skipper of a sailing ship." Today the art of building ships and boats in the traditional style is virtually nonexistent and is seen only in the repairing of small wooden vessels. Skopelos cannot support its population with locally produced food and goods. Most of what is used and consumed must be imported by ship from the mainland. Prices for food and consumer goods reflect the added expense of transportation. Therefore purchases of food and drink run 10 percent higher in Skopelos than on the mainland. Most building materials, including sand, must also be imported. Gasoline or petrol costs are, at minimum, 15 percent higher than on the mainland. Skopelos is a matrilineal society. Wealth is passed on via the female line. By custom, the parents of each Skopelitan bride provide the new couple with at least a house and some property. The house and property remain in the bride's name. This custom is particularly insular as in most other parts of Greece, especially on the mainland and Crete, wealth is patrilineal. Local food production Olives and olive oil: Olive oil plays a role in the Skopelos diet, being the basis of all recipes of traditional cuisine. The most prevalent olive is the "Pelion" variety, larger and rounder than the "Kalamata". For eating the olives are cured