| Summary: | The dorsoventrally flattened morphology of benthic ray and flatfish species is perhaps assumed to be a constraint on their locomotory ability, suggesting these sit-‐and-‐wait predators may exhibit reduced movement and low activity with all species exploiting similar niches. Advancing our understanding of ray and flatfish movement behaviour in relation to the environment is required however, because many commercial and non-‐ commerical populations are threatened by demersal fisheries. The movement patterns and behaviour of the electronic tagged ray species blonde ray Raja brachyura and spotted ray Raja montagui, and benthic teleosts turbot Psetta maxima and plaice Pleuronectes platessa, were investigated off southwest Britain. Mark-‐recapture data showed some evidence for site fidelity or increased residence time in preferred locations to some degree in all species investigated. Time-‐series of waiting times (intervals between periods of activity) were analysed statistically, revealing complex movement patterns and behavioural structure over a wide range of temporal scales. Overall, R. brachyura displayed greater horizontal and vertical ranging behaviour with longer waiting times than R. montagui, who inhabited deeper more restricted depths. Comparatively, however, teleosts showed more extensive vertical ranging and much shorter waiting time behaviour, with P. maxima displaying surface swimming, whilst P. platessa performed substantial circa-‐diel and tidal rhythms. The differences in behaviour patterns observed was attributed to feeding niche differences, among intraspecific variation such as sexual segregation and ontogenic changes. This integrated statistical approach to understand the behavioural strategies of these sit-‐ and-‐wait predators helps to assess aspects of behaviour such as decision-‐making (waiting time between activities) in relation to habitat availability and quality. A deeper understanding of spatiotemporal movements and behaviour, including where species are distributed, how long they stay there and why, will inform better management of populations. Faculty of Science
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