Climate Invasives --- MINIMIZING THE NEGATIVE EFFECTS OF CLIMATE CHANGE-INDUCED SPREAD OF INVASIVE ALIEN SPECIES TO MARINE PROTECTED AREAS

Aquatic invasive species are one of the biggest threats to biodiversity in the oceans. One of the main measures within marine strategies to preserve biological diversity is to establish marine protected areas (MPA). MPAs are areas with high biological diversity, and it is therefore important to establish effective management strategies for these areas. This project will investigate the climate-induced spread of invasive alien species (IAS) to MPAs in the North-East Atlantic (North Sea, Skagerrak and Kattegat). In the area between Denmark, Sweden and Norway, several ocean current systems merge and maritime traffic is intense. A regional approach will be developed with the aim of producing a general concept for transnational mitigation work regarding invasive alien species. The samples are now analyzed in two ways, partly with a technique to find individual species, partly to scan all species in the surroundings. The method for detecting single species generally gave weak signals for the desired species, which indicated that the method can be improved. The analysis of the data from the broad species scan indicates that the method used is robust. The results say that while some invasive species are detected in new places, including in or near marine protected areas, most are not yet found to have spread much beyond their first recorded distribution in the investigated area. New samples from 2025 are being analysed this fall which will bring up-to-date data and an understanding on how the last two years of climate change has had an impact on recent invasive species distribution.

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Invasive alien species are one of the biggest threats to the earth's biodiversity. Human activities such as transport and trade lead to more and more organisms being moved to new areas on earth where they can establish themselves and potentially become invasive. Climate change leads to the earth's climate zones moving towards the poles, which in turn leads to range shifts in many marine and terrestrial species. Climate change-induced range-shifts can lead to alien species spreading more easily and faster to new areas and that they more easily establish themselves in the new areas and become invasive as they negatively affect the local ecosystems. The established invasive species can then negatively affect the new area's ability to withstand climate change, which can lead to a further increased risk of the establishment of new alien species in the area, creating a negative spiral that leads to an accelerating loss of the native biodiversity. Protected areas can however offer a refuge for threatened species from the negative impacts of invasive alien species which makes it even more relevant to concentrate limited resources for management and control measures against IAS in protected areas. On land it has been difficult to protect for example Natura 2000 from invasive species as the introductions are driven by human activities. In the marine environment this is even more challenging as dispersal of species not easily can be followed visually, but instead require targeted monitoring efforts. This project presents methodologies that will (i) predict new invasions, (ii) optimize early detection, and (iii) minimize the negative effects of climate change-induced spread of invasive alien species to Marine protected areas.