The vulnerability of natural resources awareness of various governments and intergovernmental organizations have increased considerably, which has led to introduction of various measures aimed at improving the sustainability of fishery resources. Scientific investigations and discovery pave the path to policy changes at socio-economic and political level for effective fishery management. Marine and fisheries scientists are increasingly using advanced tools to better understand and model their systems to bridge the gap in knowledge of fish behavior and distribution. In addition to the scientific investigations, traditional local knowledge sources provide information about declines and changes in fishing fleets, fisheries management and stock assessments in data-poor situations. This book describes the advances in fishery sciences technology, which collectively lead to assessing fish reproductive potential and dispersal in land and marine fishes for economic and ecological advancements.