Plymouth scientists record rapid changes to marine life
Some "dramatic" changes in marine life have been recorded by scientists in Plymouth, Devon.
Researchers at the Marine Biological Association said there had been "rapid transformation" in the distribution of barnacles, molluscs and seaweed.
By studying active sites around the South West coast, they have discovered some reproductive cycles have advanced by up to three months.
The scientists believe climate change could be responsible.
Their research has indicated a "battle" between colder and warmers species - with the warmer ones winning.
Dr Nova Mieszkowska, from the Marine Biological Association, told BBC News: "I think what's different is the rate of change and the extent and magnitude of these species increasing in abundance and extending their limits."
Slipper limpets (crepidula fornicata), which have been appearing far more frequently in recent years in the South West, could impact on local mussel beds, she said.
"The problem is they form these big fornicating stacks which produce an awful lot of faeces and mess and the water then becomes cloudy with muck," she added.
Marine scientists, who have also been collecting data across Europe, said some of the changes that had taken place recently cannot be explained as routine and could have an impact on local fish stocks.
Warm water sea snails have extended their northern range limits around the UK by up to 50km per decade - about three times as fast as terrestrial species.
However, the southern range edge of the cold water tortoiseshell limpets has retreated north by almost 1,000km, with breeding populations now only recorded in northern Scotland.
Dr Mieszkowska said the information collected over the past 50 years represented one of the most comprehensive data sets of its kind.
"We can see how marine plants and animals have responded to natural warming and cooling of the climate in the past and that allows us determine the scale and speed of response to the unprecedented rapid warming that we are seeing now," she said.
"Not all species are negatively affected - those with origins in warmer waters of Europe are expanding their distributions north as the environment becomes more favourable.
"For some native species, however, the warming is bad news, causing them to fail to reproduce and survive near their southern range edges."