Scotland's seas are economically productive. Official figures show that the core marine sector, less the extraction of oil and gas, contributed £3.6 billion of Gross Value Added (GVA) in 2008 (at 2009 prices), about 3.5% of overall Scottish GVA. About 39,800 people were employed, 1.6% of Scottish employment. The extraction of oil and gas had a GVA of £13.3 billion in 2007 (at 2009 prices).
Fishing takes place in all Scottish sea areas but some, such as Hebrides, North Scotland Coast and East and West Shetland, are far more economically productive than others. Aquaculture, both finfish and shellfish, predominates on the west coast and the islands.
Sixteen major ports handle about 98% of all port traffic with liquid bulk, mainly oil and gas, accounting for 69%. There is significant commercial shipping both to ports and for transit through Scottish waters, as well as domestic and international ferry activity. The seas are also used extensively by the Royal Navy and other armed forces, for exercises and operations, sometimes including international partners.
Other activities include cooling water abstraction for power stations and the disposal of treated urban waste water, industrial effluent and dredge spoil. Seabed telecommunications cables carry millions of internet and phone call connections, thereby providing a major communications network.
The seas are also used for leisure and recreation, particularly sailing, angling and other sporting activities. Scotland's historic environment and natural and cultural heritage attract many tourists.
The enormous potential of marine renewable energy generation from offshore wind, waves and tides has started to be harnessed. There is also potential for storage of carbon dioxide under the seabed, in 'carbon capture and storage' schemes.