PDF hosted at the Radboud Repository of the Radboud University Nijmegen The following full text is a publisher's version. For additional information about this publication click this link. http://hdl.handle.net/2066/175780 Please be advised that this information was generated on 2017-10-13 and may be subject to change. Build it and who will come? Alien species risk assessment in river catchment management Matthews J.M. (2017). Build it and who will come? Alien species risk assessment in river catchment management. PhD thesis, Radboud University, Nijmegen, The Netherlands. © 2017 Jonathan Matthews, all rights reserved ISBN: 978-94-6233-721-3 Cover photo: The spread of the plague by haystackengineering (creative commons license) Print: Gildeprint, Enschede Build it and who will come? Alien species risk assessment in river catchment management Proefschrift ter verkrijging van de graad van doctor aan de Radboud Universiteit Nijmegen op gezag van de rector magnificus prof. dr. J.H.J.M. van Krieken, volgens besluit van het college van decanen in het openbaar te verdedigen op donderdag 5 oktober 2017 om 12:30 uur precies door Jonathan Matthews geboren op 23 juni 1973 te Epsom, Engeland Promotoren: Prof. dr. R.S.E.W. Leuven Prof. dr. ir. A.J. Hendriks Copromotor: Dr. G. van der Velde Manuscriptcommissie: Prof. dr. M.A.J. Huijbregts (voorzitter) Prof. dr. L. Posthuma Dr. ir. J.L.C.H. van Valkenburg Paranimfen: Dr. A. Benítez López Dr. R. Oldenkamp Contents 1 General introduction ...................................................................................................... 1 1.1 Background .......................................................................................................... 2 1.2 Aims and scope .................................................................................................... 8 1.3 Thesis outline ..................................................................................................... 10 2 Lessons from practice: assessing early progress and success in river rehabilitation ... 13 2.1 Abstract .............................................................................................................. 14 2.2 Introduction ........................................................................................................ 14 2.3 Methods .............................................................................................................. 16 2.4 Results ................................................................................................................ 19 2.5 Discussion .......................................................................................................... 24 3 A new approach to horizon-scanning: identifying potentially invasive alien species and their introduction pathways ........................................................................................... 31 3.1 Abstract .............................................................................................................. 32 3.2 Introduction ........................................................................................................ 32 3.3 Materials and methods ....................................................................................... 35 3.4 Results ................................................................................................................ 42 3.5 Discussion .......................................................................................................... 46 4 Inconsistencies in the risk classification of alien species and implications for risk assessment in the European Union ...................................................................................... 53 4.1 Abstract .............................................................................................................. 54 4.2 Introduction ........................................................................................................ 54 4.3 Methods .............................................................................................................. 56 4.4 Results ................................................................................................................ 61 4.5 Discussion .......................................................................................................... 65 5 Rapid range expansion of the invasive quagga mussel in relation to zebra mussel presence in the Netherlands and Western Europe ................................................................ 73 5.1 Abstract .............................................................................................................. 74 5.2 Introduction ........................................................................................................ 74 5.3 Methods .............................................................................................................. 75 5.4 Results ................................................................................................................ 79 5.5 Discussion .......................................................................................................... 90 6 A dominance shift from the zebra mussel to the invasive quagga mussel may alter the trophic transfer of metals ..................................................................................................... 97 6.1 Abstract .............................................................................................................. 98 6.2 Introduction ........................................................................................................ 98 6.3 Methods .............................................................................................................. 99 6.4 Results .............................................................................................................. 102 6.5 Discussion ........................................................................................................ 105 7 Synthesis ................................................................................................................... 111 7.1 Introduction ...................................................................................................... 112 7.2 Invasive species risk assessment in river rehabilitation planning..................... 112 7.3 Implications of invasive species assessment to rehabilitation planning ........... 113 7.4 Assessing the potential for alien species establishment as a result of rehabilitation interventions ............................................................................................ 117 7.5 Conclusions ...................................................................................................... 126 7.6 Recommendations ............................................................................................ 127 Appendices ........................................................................................................................ 129 Literature cited ................................................................................................................... 139 Summary ............................................................................................................................ 175 Samenvatting ..................................................................................................................... 181 Acknowledgements............................................................................................................ 187 Curriculum vitae ................................................................................................................ 193 List of publications ............................................................................................................ 197 Chapter 1 1 General introduction General introduction 1.1 Background 1.1.1 Alien species and their impacts Invasive alien species (IAS) are seen as an important cause of ecosystem changes, leading to major ecological and socio-economic impacts. In general, IAS are the second leading cause of global biodiversity loss, after loss of habitat (Moyle et al. 1986; Vitousek et al. 1997; García-Berthou et al. 2005). It has been estimated that IAS have contributed to nearly 40% of all animal extinctions since the 17th century where a cause has been established (Secretariat of the Convention on Biological Diversity 2006). The Secretariat of the Convention on Biological Diversity (2010) identified more than 542 alien species in a sample of 57 countries, including marine and freshwater fish, vascular plants, birds, mammals and amphibians, with a demonstrated impact on biodiversity. An average of over 50 such species were identified per country, ranging from nine to over 220. These figures are almost certainly underestimates as they exclude alien species whose impacts have not yet been assessed, neglect certain species groups such as bacteria, commensals, symbionts and parasites, and only include countries where data on alien species is available (Secretariat of the Convention on Biological Diversity 2010). In the European Union and other European countries, there are approximately 12,000 known alien species in the environment and around 10 to 15% of these are estimated to be invasive (European Commission 2014). Ecological impacts relating to species invasions occur at the individual, population, species, community and ecosystem level and occur through a variety of mechanisms including facilitation, competition, herbivory,