Environmental factors associated with invasion: modeling occurrence data from a coordinated sampling programme for Pacific oysters

This is the post print version of the article. The final publication is available at Springer via http://dx.doi.org/10.1007/s10530-013-0452-9Documenting establishment and spread of invasive species requires extensive co-ordinated sampling programmes. Identifying the factors promoting or inhibiting local establishment of an invasive species can improve capacity to predict further spread and underpin strategies to limit spread. Here, a structured sampling programme was used to assess the current distribution of feral populations of Pacific oysters, Crassostrea gigas, in Ireland. Sixty-nine sites were sampled using a standardised protocol combining semi-quantitative and quantitative approaches. Sites were chosen to represent variation in proximity to aquaculture and a range of environmental variables. Oyster populations were found at 18 locations, with densities ranging from single individuals to nine individuals per m2. The broad size range of oysters found is indicative of more than one recruitment event. Logistic regression indicated that feral oysters were positively associated with the presence of hard substrata or biogenic reef, long residence times of embayments and large intertidal areas. There was also a tendency for oysters to occur disproportionately in bays with aquaculture, but >500 m from it. Small-scale analysis within sites showed that oysters were almost exclusively attached to hard substrata and mussel shell. The approach taken here provides a rigorous repeatable methodology for future monitoring and a detailed basis for the prediction of further spread

Water Framework Directive: marine ecological tools for reference, intercalibration and classification (METRIC): final report for the ERTDI-funded project: 2005-W-MS-36

Water quality monitoring programmes exist in many of the Member States throughout the European Union (EU). With the implementation of the Water Framework Directive (WFD, Council Directive 2000/60/EC) all Member States must harmonise their national monitoring methods for each common metric (parameter indicative of a biological water quality element) used to determine the state of the aquatic environment to ensure consistent and comparable classification results for all biological community quality elements used (WFD Annex V, 1.4.1). The Marine Ecological Tools for Reference, Intercalibrationand Classification (METRIC) project, therefore, was designed specifically to support the Irish role in the EU Intercalibration Exercise of biological quality elements (BQEs) in order to set harmonised ecological quality criteria for the assessment of water quality in the transitional and coastal (TraC) waters of Europe. The BQEs investigated by METRIC included: Plants (phytoplankton, macroalgae andangiosperms), Benthic macroinvertebrates (soft-bottom habitat), Fish (estuarine).Environmental Research Sub-Programme of the National Development Plan (NDP), the Inter-Departmental Committee for the Strategy for Science, Technology and Innovation (IDC-SSTI), and EPA core funding and co-funding by economic sectors