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Light pollution along coastlines and from passing shipping are disrupting the behaviour of marine animals and altering underwater habitats.

New research has shown that artificial light can attract certain species to coastal areas while forcing others away.

The study found that light pollution was particularly prone to attracting marine invertebrates that can cause fouling of marina, dockyards and shipping.

Bright lights such as Blackpool's illuminations (above) are altering the balance of marine life on the coast

Other species such as sea squirts and sea bristles tend to avoid areas that are illuminated by artificial lights.

The findings suggest that light pollution may be altering the balance of marine life around coastal communities, oil rigs and shipping lanes.

The researchers, based at the University of Exeter and Bangor University, said that light pollution could also have an impact on coral reefs, particularly in tropical waters.

Dr Katherine Griffith, an ocean scientist at Bangor University who was one of the authors of the study, said: 'With urbanisation on the increase, many coastal areas around the globe will become vulnerable to the effects of artificial light pollution.

'Therefore, further research on how artificial light may disrupt marine communities is vital if we are to mitigate these impacts.'

Many marine invertebrate larvae use light as a cue to help them search for suitable habitats to settle, grow and reproduce.

The researchers, whose work is published in the journal Royal Society Biology Letters, used LED lights in a laboratory to examine how they impacted the movement of the larvae of 47 different marine invertebrates.

They found species such as keel worms, which attach themselves to the bottom of ships and other marine structures such as piers, were significantly higher in number in areas that were lit up by white LED lighting.

Amphipod crustaceans like Corophium, which tend to inhabit mudflats, were also significantly higher in areas lit up by the lights.

As many of these species provide important food sources for fish and other marine animals, the light pollution can also effect the spread of other larger animals, the researchers warned.

Dr Tom Davies, from the University of Exeter, said legislation may be needed to help reduce the impact of light pollution in the future. 

These corophium amphipods live on coastal mudflats but are attracted to bright artificial lights, the study found, which can affect the diet of other larger animals who feed on them

The bright lights from coastal communities, like those in Plymouth shown above, can force some species out of the water around them

He said: 'We know that artificial light at night alters the behaviour of many marine animals but this is the first study to show that it can disrupt the development of ecological communities in the marine environment.

'Further research is urgently needed to assess what level of light can be considered "safe" so that legislation can be put in place to minimise future light pollution from new and existing developments.'

Dr Stuart Jenkins, who also took part in the work at Bangor University, added: 'This is an important first step in developing understanding of the way artificial light may be affecting marine coastal assemblages.

'Our research showed that levels of artificial light, commonly found in urbanised and developed coastal areas, can have important effects on the development of communities inhabiting hard surfaces in shallow water.'

Infrastructure like docks (above) and oil rigs can produce significant amounts of light pollution on the coast

Sea squirts like Botrylloides leachi (above) were significantly reduced in areas polluted by artificial light