Invasive Seaweed Types Spreading Across Europe

Tuesday, 18 May 2010

Important Research conducted at NUI Galway published by Royal Society
A European project involving Irish scientists from NUI Galway and Queen's University Belfast has found that recently introduced seaweed types from areas such as Japan and California are spreading more rapidly in Europe than ever before. Professor Mark Johnson with The Martin Ryan Institute (MRI) at NUI Galway is the corresponding author on a paper which has gone online in the Proceedings of the Royal Society. The essence of this paper denotes how particular species of seaweed introduced to Europe have spread. This includes an increasing rate of spread in recent years. There are over 500 seaweed types in Ireland, and some 126 non-native species from Asia and the US have been recorded in Europe over the past century. The research paper published by the Royal Society (Fronts, Jumps and Secondary Introductions Suggested as Different Invasion Patterns in Marine Species, with an Increase in Spread Rates Over Time) is one of the outputs from a project known as ALIENS (Algal Introductions to European Shores). The research ran over four years and focused on the ecology, spread and impacts of introduced seaweeds. Professor Johnson remarked, "Research of this nature has relevance for marine and aquaculture policy into the future. This involves continuing with existing approaches to educate boat owners to clean their boats in order to stop the spread of invasive species of seaweed and protect native varieties. There are also efforts to control the spread with restrictions throughout the aquaculture industry. At present, some invasive species of seaweed can crowd out or displace native plants. It is important that we continue to protect our native species." PhD student Frederic Mineur, who worked with Professor Johnson on the project reconstructed the historical spread of seaweed dating as far back as 200 years ago. Species of seaweed introduced to a region often spread out from the point of introduction at a relatively even rate. However, other patterns can also occur. Most seaweeds introduced to Europe appear to have been introduced at more than one point or have unpredictable long range dispersal. Looking at the spread patterns over time, the rate of spread appears to be increasing for more recent introductions. This could be because there are more opportunities for seaweeds to associate with carriers like shipping or aquaculture. Another possibility is that the resistance of coastal environments to novel species' introductions is declining. This current study is complete but there are plans to extend the work to understand more about the dispersal of introduced species. There may be particular routes that more than one species has travelled by within Europe and conversely there may be barriers within Europe to the spread of species. To access the article featured in the Royal Society, follow the link below.

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