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An increasing number of regulatory tools aiming to impose preventive and control actions against invasive species are currently being developed in Europe. Both species prioritization and the choice of best preventive and potential control actions to reduce the risk require robust and transparent risk assessment. Two different generic tools, available from http://ias.biodiversity.be, have recently been developed in Belgium to help decision makers reaching these goals, i.e. a quick screening prioritization process (Harmonia+) and a detailed risk assessment scheme. Both tools may be applied to any non-native organism irrespective its taxonomic affiliation and encompass an evaluation of the probability of organism entry, establishment, spread, and of the potential and magnitude of environmental, economic and social consequences including plant, animal and human health. Harmonia+ is a quick screening tool that may be used for different purposes (D’hondt et al. 2014): (i) the elaboration of priority lists of invasive species that are established or could potentially establish in an area, (ii) the fulfillment of rapid assessment to help conservation managers to prioritize actions when a new non-native organism is found in the wild and (iii) the identification of non-native species with the highest priority for in-depth and time consuming risk analyses and (iv) the scoring of probability and magnitude of the different elements included in those risk analyses.The detailed scheme for invasive species risk analysis is based on the recommendations of the international standards for pest risk analysis for organisms of quarantine concern produced by the Secretariat of the International Plant Protection Convention. It follows a process defined by two main stages, i.e. the risk assessment stage itself and the risk management stage, which involves identifying options for reducing the identified risks. This detailed analysis is especially valuable to know whether trade restrictions could be considered as adequate and efficient to reduce the risk.The output of the risk assessments based on these new tools will be presented and discussed for five emerging non-native species in Belgium (water primrose, red swamp crayfish, American bullfrog, sacred ibis and raccoon dog). Different recommendations and priorities for decision making will be provided for the different species based on the outcome of these analyses. Potential uses for the selection of species of EU concern in the framework of the new EC proposal of Regulation on the prevention and management of the introduction and spread of IAS in Europe will also be discussed.

In dit eindrapport wordt het kader m.b.t. de inzet van vrijwilligers voor de uitvoering van gestructureerde meetnetten uitgewerkt. In hoofdstukken 1 en 2 wordt basisinformatie aangereikt omtrent de taxonomische scope en de monitoringsmethoden. Hoofdstuk 3 beschrijft globaal de data die voor de HRL/VRL-rapportering van 2013 werden gebruikt. In de hierop volgende hoofdstukken (4-8) wordt dieper ingegaan op de eigenheid van de vrijwilligerswerking. Specifieke aandacht gaat hierbij naar de betekenis van losse waarnemingen (Hfdst 4), het toetsingsproces van de blauwdrukken (Hfdst 5), specifieke aandachtspunten voor (Hfdst 6), en de dynamiek van deze werking (Hfdst 7). Vervolgens wordt een conceptueel kader geschetst voor de begeleiding en ondersteuning van vrijwilligers bij meetnetmonitoring, en een concreet voorstel gelanceerd (Hfdst 8). Hierop worden de bestaande natuurdatasystemen in Vlaanderen in kaart gebracht, alsook de bestaande en geplande samenwerkingsverbanden tussen Natuurpunt en de overige vrijwilligersorganisaties (Hfdst 9). De toekomstige meetnettenapplicatie wordt hier ook kort toegelicht. In hoofdstuk 10 wordt een overzicht gegeven van de relevante aspecten voor de meetnetbegroting.

Female polymorphism is observed in various animal species, but is particularly common in damselflies. The maintenance of this polymorphism has traditionally been explained from frequency and density dependent sexual conflict, however, the role of abiotic factors has recently attracted more interest. Here, the role of ambient temperature in shaping life-history was investigated for the three female morphs of Ischnura elegans (Vander Linden) (Zygoptera: Coenagrionidae). Eggs were obtained from the three mature female morphs for two populations in the Netherlands. Using a split-brood design, eggs of both populations were divided between a cold and a warm treatment group in the laboratory, and egg survival and hatching time were measured. Significant thermal plasticity was found in both hatching time and egg survival between both temperature treatments. However, individuals born to mothers belonging to different colour morphs did not differ in their response to temperature treatment. Independent of colour morph, clear differences in both life-history traits between the populations were found, suggesting local adaptation. Specifically, individuals from one population hatched faster but had lower egg survival in both thermal regimes. The selection force establishing fast hatching could be (facultative) bivoltinism in one of the populations compared to univoltinism in the other. This would be in line with the more southern (and more coastal) location of the presumed bivoltine population and the inverse relation between voltinism and latitude known from earlier studies. However, other natural selection forces, e.g. deterioration of the aquatic habitat, may also drive fast hatching. Keywords

Female polymorphism is considered to be maintained through negative frequency-dependent selection imposed by costly male harassment. However, few studies have questioned whether male harassment negatively affects female morph success and does so differently for female morphs, especially in the wild. In the present study, we quantified female morph condition (relative body mass and energy reserves) for a colour polymorphic damselfly under natural conditions and evaluated these measures against variation in proxies of male harassment population density and operational sex ratio) and ambient temperature. Differences in protein content between female morphs were detected and the variation in condition could partly be explained from concomitant variation in proxies of male harassment. Specifically, the relationship between protein content and operational sex ratio differed between morphs in that the negative effect of male harassment was more pronounced in gynomorphs than in andromorphs. In addition, ambient temperature affected the body mass and protein content of female morphs differently, with andromorphs having higher condition values in favourable weather conditions, whereas, for gynomorphs, the patterns tended to be opposite. In conclusion, the results obtained in the present study suggest that male harassment negatively and differentially affects female morph success. Future studies should aim to elucidate whether the observed effects of ambient temperature contribute to the maintenance of the polymorphism.

Recently, an overview of the diversity, abundance, distribution and morphological characteristics of spp. of the genus Nesobasis, endemic to Fiji, was presented for spp. occurring on the 2 largest islands of the archipelago: Viti Levu and Vanua Levu. Here this knowledge is extended by providing more extensive diversity and abundance data for the island of Vanua Levu, as well as for 4 smaller islands in Fiji: Taveuni, Koro, Ovalau and Kadavu. Previous research indicated that the Nesobasis spp. inhabiting Viti Levu and Vanua Levu are unique, with these islands having no species in common. The new data confirm this proposal and also show that smaller islands in proximity to these 2 larger islands usually contain a subset of large island's Nesobasis fauna. The isalnd of Koro, however, is unusual in that, while its Nesobasis spp. are predominantly those found on Vanua Levu, it also harbours N. rufostigma, a sp, occurring on Viti Levu. Further, N. recava is endemic to Kadavu and is not found on Viti Levu, the nearest large island. Species richness is higher on large than small islands while mean species abundances were consistently higher on large islands compared to small islands. The pattern of distribution and speciation in this genus is quite complex, and is the subject of ongoing research.