Novel methods for quantifying movement behavior of free-ranging fish from telemetry data

摘要: In recent decades, technological progress in the field of biotelemetry has allowed collection of vast amounts data on movement free-ranging marine animals and recently there have been great advances analysing from tags that allow observation complete animal tracks. One most common low-cost tools for tracking animals, however, are automated acoustic arrays, which often do not record complete tracks but provide presence/absence tagged at fixed locations. The development of quantitative methods these lagged behind in the field. This thesis applies novel quantifying behaviour highly mobile free-ranging teleosts elamsobranchs using answers ecological questions management relevance tropical tuna (Yellowfin Thunnus albacares) a temperate shark species (Broadnose sevengill Notorynchus cepedianus). Additionally, pop-up satellite archival tag (PSAT) analysed shark species, to put findings analysis into context the animals’ large-scale behaviour. The two datasets represent different types receiver array designs: For the study, individual receivers were deployed ecologically significant locations (fish aggregating devices, FADs) determine residency between For as multiple curtains opposite shorelines detect passes through general movement patterns within coastal area. Network applied both quantify co-occurrence of individuals given location relative importance each the animals. former, we adapted association indices social network to quantify temporally explicit joint occurrences individuals. latter treated the number transitions measure connectivity them. The network approach was well suited type array used study considerable improvement over traditional measures cooccurrence which only include either spatial or temporal dimension, both. It provided new insight dynamics aggregations FADs how they may be linked between-FAD movement. We observed large interannual variation in movement rates FADs, corresponding variability mean number spatio-temporal associates stability of associations. When high, associations FAD decayed to randomness three times faster than when lower. This raises the possibility if sufficiently close fish perform frequent between-FAD movements, school mixing may increased cohesion reduced. data, compared results Markovian movement model estimated counts transitions. Specifically, tested suitability of the determining whether differences behaviour between males females established PSAT mirrored their space-use during summer residency. Both Markov chain analysis showed space-use male female broadnose sharks, however, rankings geographic areas differed two approaches. indicated but also periods, not accounted by analysis, important identifying priority the sharks. Determining interact move environment relatively understudied area, lacking quantitative analytical methods. various novel approaches individuals use space, deepening our understanding link