Understanding fish-habitat associations using video observations and sonar imaging

Planning for resilience is now a catch cry of many marine conservation programs and initiatives. These efforts are striving to inform conservation strategies for marine regions to ensure they have inbuilt capacity to retain biological diversity and ecological function in the face of global environmental change – particularly changes in climate and resource exploitation. A fundamental step in these strategies is to understand the distribution of species’ (or other biological entities) throughout the focal region. However, in the absence of direct biological and ecological information for many marine species, scientists are increasingly using spatially-explicit predictive modelling approaches. Through the improved access to multibeam echosounder (MBES) data and underwater video technology these models can provide spatial predictions of the most suitable regions for an organism at resolutions previously not possible. This thesis was motivated by the recognition of the potential role of species distribution models in managing marine fish species and their habitats. This thesis sets out to address four interlinked ideas in consecutive chapters, with their justification and outcomes briefly detailed below.