Marine Scotland Reports - Marine Environment - Scotland's Marine Atlas
dataset
https://portal.medin.org.uk/portal/start.php?tpc=012_Marine_Scotland_FishDAC_856
Scotland’s vision is for ‘clean, healthy, safe, productive, biologically diverse marine and coastal environments, managed to meet the long term needs of nature and people’. This assessment of the condition of Scotland’s seas has been based on scientific evidence from data and analysis, supported by expert judgement.
Climate Change and Ocean Acidification
The climate shows considerable variation over short and long timescales. However, in recent years there has been a marked increase in the concentration of carbon dioxide (CO2) in the atmosphere of the Earth and, at the same time, sea surface temperature has risen as have sea levels. Changes in the biological components of the seas have been observed including earlier plankton blooms, a northward movement of some species and a reduction
in seabird populations, all of which have been linked to climate change.
At the same time, the seas are becoming more acidic, the consequences of which, especially for calcareous organisms, could be significant. Reductions in the emissions of greenhouse gases are required and Scotland has set ambitious targets. However, even with such reductions, it is highly likely that further impacts of climate change on the marine environment will be observed.
Clean and Safe
Scotland’s seas are mainly clean and safe, although there are some localised areas where there is contamination or hazards to human health. For example, sediments in several harbours and estuaries remain contaminated with hazardous substances, a legacy of past industrial discharges. Water quality in the Forth and Clyde estuaries is compromised by discharges of industrial effluent and treated sewage although effluent treatment has
improved resulting in returning populations of residential and migratory fish. The use of historical contaminants such as polychlorinated biphenyls (PCBs) and tributyl tin (TBT) has been banned, and monitoring continues to assess their continued environmental decline.
Information is being gathered on a range of other contaminants, including endocrine disrupters and brominated flame retardants, to assess their environmental impacts. Diffuse inputs of nutrients and bacteria have given rise, respectively, to some localised issues in small east coast estuaries and at bathing beaches. Action plans have been put in place to tackle these issues. Concerns such as marine litter and underwater noise have
become more broadly recognised and will be addressed through the operational response to the Marine Strategy Framework Directive. Generally the effects of noise remain unquantified and unknown.
Healthy and Biologically Diverse
Scotland’s seas support a diverse array of habitats and species and contain nationally and internationally important populations of certain species such as the northern feather star, the burrowing sea anemone, the northern sea fan and cold water corals.
There is evidence that certain habitats have been impacted, for example shallow and shelf subtidal sediments (including burrowed mud habitats). This stems largely from the effects of fishing over large areas of the seabed and more localised impacts from activities such as aquaculture.
The low abundance of some demersal commercial fish species across the west coast of Scotland is a major concern and is being addressed through various initiatives. Improved knowledge of fishing activity and its impact on the marine environment would be beneficial.
Establishment of new fisheries should only be undertaken following careful assessment of the viability and future sustainability of the fishery, especially given the sensitivity of some, particularly deep water, species to fishing and against a background of historic over-exploitation.
Sharks, skates and rays face further declines and are severely depleted all around the coast, although the number of sightings of basking sharks has increased in recent years especially in the Minches and Malin Sea. These declines are largely the consequence of historically unsustainable catches in both target and non-target fisheries and their long-lived, very low fecundity life cycle. Many of these, for example, porbeagle and
common skate, can no longer be targeted commercially.
Populations of some seabirds, harbour seals and some fish species have declined. Possible reasons include climate change, a number of different human activities and competition from other species. These declines may be associated with broader changes in the food web. For example, the decline in availability of sandeels has had a major influence on recent changes in seabird numbers on the east coast and in the Northern Isles.
Although, in general, the current assessment for cetaceans suggests there are no specific concerns, this has been made against a background of a very high level of uncertainty and little power to detect concerns if they currently exist.
Productive
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.
Also see http://www.scotland.gov.uk/Resource/Doc/345830/0115128.pdf for maps and further details.
20110316