We rely on the sea for a huge range of products, including seafood, pet food, oil, sand, and substances used in ice cream, washing powder and toothpaste! We also use it to dispose of our waste, to transport goods and people and to provide for our recreation. The Irish Sea provides for us in many ways, but it also provides a home to wild animals and plants. Human demands on the sea have the potential to threaten sea life through the impacts of waste-disposal, over-fishing, coastal development and extraction of minerals.

Cables
Numerous telecommunications cables run across the bed of the Irish Sea. There is some evidence that sharks and rays are attracted to unshielded electromagnetic fields.

Effluent
Since the industrial revolution in the 19th century the Irish Sea has been used as a convenient site for disposal of liquid waste, including sewage and unwanted by-products of industrial processes such as mining, manufacturing, nuclear waste reprocessing and energy generation.

The treatment of sewage and industrial waste discharged into watercourses and directly into the sea has improved steadily since the latter half of the 20th century. Sewage and other waste is no longer dumped offshore. However, the legacy of past practices still remains, particularly in the case of 'heavy metal' pollution by compounds of lead, cadmium, arsenic and other poisons, which bind into sediment on the seabed.

The levels of agricultural effluent flowing off fields into rivers and thence the sea has increased markedly over the same period, leading to increased fertility of inshore waters and associated algal blooms and de-oxygenation of seawater, particularly in enclosed bays and estuaries.

Products in every day use in our homes may contain a wide variety of inorganic chemicals and organic compounds. These are also flushed or washed away after bathing or showering, or disposed of directly into the drains.

These substances discharged into the sea may combine together in ways that make it difficult to predict their ultimate effect of the marine environment. Some may remain indefinitely in the seawater, the seabed, or the flesh, fat and oil of sea creatures.

See also:
WWF-UK: http://www.wwf.org.uk/filelibrary/pdf/ma_waste_wa.pdf
Irish Sea Forum: http://www.liv.ac.uk/~isf1/semsums/sem10sum.html
Surfers Against Sewage http://sas.org.uk

Fisheries
Commercial fisheries may damage the marine ecosystem directly, through competition and increased efficiency leading to unsustainable demands on target species, or indirectly through by-catch and the impact of fishing methods on the seabed. The activities of different fishing sectors may also impact on one another's success.

The Marine Conservation Society has published 'The Good Fish Guide', giving advice on choosing 'environmentally friendly' fish to eat. You can order a copy at www.mcsuk.org.

Marine Aggregate Extraction
Currently, sand and gravel taken from the sea make up 21% of the supply in England and Wales (no figures found for other countries around the Irish Sea). These materials - known as marine aggregate - are used by the construction industry (e.g. in concrete) and for replenishing beaches that have eroded away.

Marine aggregate extraction inevitably has drastic short-term effects on marine wildlife and habitats in the area directly affected, and we are only beginning to understand the process of recovery. The Wildlife Trusts are working with the British Marine Aggregate Producers' Association to develop a better understanding of the industry and its impacts.

At present, the conservation of offshore sand and gravel biotopes in the Irish Sea is wholly reliant on the environmental management of marine aggregate extraction and other industries, as neither the Habitats Directive nor Biodiversity Action Planning have been actively applied in this environment. Marine Spatial Planning is a developing tool that might be applied to ensure more effective, integrated management and protection of marine biotopes.

Water-based Recreation
Increasing leisure time can lead to increased contact with and understanding marine wildlife. However, construction of marinas and an increase in marine traffic, particularly motorised vessels, has the potential to increase pressure on marine wildlife. This can be through direct contact - as is the case with dolphins, porpoises, seals and basking sharks, or indirectly through increased marine pollution and litter or loss of foreshore to "hard" development.

The Green Blue is a new environmental awareness initiative by the British Marine Federation and the Royal Yachting Association. It hopes to educate and inform the recreational boating community about its environmental impacts, emphasising how industry and users can avoid or minimise these impacts.