Non-indigenous species from a scientific point of view Arjan Gittenberger GiMaRIS Marine Research, Inventory, & Strategy solutions Institute of Biology, (IBL); Institute of Environmental Sciences (CML), Naturalis Biodiversity Center The study of non-indigenous species concerns the study of population dynamics in time and space Systematics Phylogenetics Population genetics Ecology Ethology Anthropology …Politology Species concept of Ernst MAYR, 1940 Species are: Groups of natural populations forming a reproductive community or capable of doing so, that are reproductively isolated from other such groups. Subspecies concept of Ernst MAYR, 1940 Subspecies have their own, exclusive range within that of the species, but are not reproductively isolated, so that hybridisation occurs whenever individuals of two subspecies of the same species are in contact (in a contact-zone) Subspecies A Hybrids of A & B Subspecies B Subspecies concept of Ernst MAYR, 1940 Should Mytilus edulis galloprovincialis be considered a non-indigenous species in northern Europe? Mytilus edulis edulis Hybrids Mytilus edulis galloprovincialis The mystery dripping sea-squirt Didemnum sp. ? http://woodshole.er.usgs.gov/project-pages/stellwagen/didemnum/index.htm Phylogenetics: The identity of Didemnum sp. in Didemnum sp. from Japan, Japan, North New Zealand, America, New Zealand, North America & Europe & Europe ? = Didemnum vexillum Kott, 2002 Stefaniak, L., G. Lambert, A. Gittenberger, H. Zhang, S. Lin & R.B. Whitlach, 2009. Genetic conspecificity of the worldwide populations of Didemnum vexillum Kott, 2002. Aquatic Invasions 4(1): 29-44. Population genetics: The origin of Didemnum vexillum Stefaniak, L., Zhang, H., Gittenberger, A., Smith, K., Holsinger, K., Lin, S. & R.B. Whitlatch, 2012. Determining the native region of the putatively invasive ascidian Didemnum vexillum Kott, 2002. Journal of Experimental Marine Biology and Ecology 422-423: 64-71. Primary distribution of marine non-native species to Europe Distribution directly from the place of origin, i.e. where the species is native Origin of marine non-indigenous species in The Netherlands Gittenberger, A., 2009. Risicogebieden wereldwijd en binnen het NACP. pp. 19-33, Bijlage D: 85-88. IN: Wijsman, J.W.M. & I. De Mesel, 2009. Duurzame Schelpdiertransporten. 111 pp. i.o.v. Directie Kennis, Ministry of Agriculture, Nature and Food Quality, Den Haag, The Netherlands. Japanese oysters: Crassostrea gigas Ecosystem engineering species… Primary distribution in the past [1] Shellfish transports: Japanese oysters from Japan [2] Ballast water [3] Hull fouling [4] Natural distribution capacities Primary distribution at present [1] Shellfish transports: Japanese oysters from Japan [2] Ballast water [3] Hull fouling [4] Natural distribution capacities Secondary distribution Distribution from an area where the species was introduced (/ is also non-native) Secondary distribution: [1] Natural distribution capacities [2] Hull fouling [3] Shellfish transports [4] Ballast water Natural distribution capacities of non-indigenous species? Oyster Rocks reefs In the 19th century & start of 20th century www.plasticmarinelitter.eu What is the role of shipwrecks in the North Sea for the distribution of hard substratum related species? 3 Expeditions North Sea Denmark 2 x Dogger Bank in 2011 & 2012 1 x Brown Ridge Dogger Bank in 2013 Germany ~ 30-50 m depth ~100 - 250 km offshore Brown Ridge UK Netherlands Highest diversity Didemnum vexillum Highest diversity … Transport vectors? Highest Shellfish diversity industry Shellfish industry Shellfish industry Shellfish industry Shellfish Shellfish industry industry Shellfish industry … TransportFisheries vectors?? Highest Shellfish diversity industry Shellfish industry Shellfish industry Shellfish industry Shellfish By Klaudie Bartelink Shellfish industry industry Shellfish industry Global warming, in an ever-changing environment Range expansion of southern European species? The jewel anemone Corynactis viridis Gittenberger, A., Schrieken, N., Coolen, J. & W. Vlierhuis, 2013. The juwel anemone Corynactis viridis, a new Order for The Netherlands (Cnidaria: Corallimorpharia). NFM: in press. The gastropod Simnia patula, a southern newcomer? Schrieken, N., Gittenberger, A. & W. Lengkeek, 2011. First record of Xandarovula patula (Pennant, 1777) in the Dutch North Sea (Gastropoda, Ovulidae). Basteria 75(4-6): 107-110. 2011-2013 North Sea expeditions >15 “new” species belonging to the autochthonous fauna of The Netherlands? Known spread and presence of marine invaders in UNESCO World Heritage area: Wadden Sea 2 rapid assessments focusing on non-indigenous species in 2009 and 2011 2009 & 2011 Wadden Sea expeditions 18 “new” non- indigenous species for the Dutch Wadden Sea Although there is no lack of hypotheses in biology related scientific disciplines like ecology and ethology, still much scientific research is needed to predict the population dynamics of non-indigenous species in time and space in the North-East Atlantic …for example aiming at gaining a better knowledge of the non-indigenous species that are already there… The scientific discipline that may provide the best predictions of future non-indigenous species dynamics in time and space is Politology, the science concerned with theory, description, analysis and prediction of political behaviour, political systems and politics broadly-construed. …. Non-indigenous species political agenda… What about that ballast water tank ? What about the fouling species on the hull? What about the stepping stone function of the shipwreck? http://anim-carton.blogspot.nl .