Amid the ongoing depletion of global fishery resources and intensifying ecological pressures, unmanned aerial vehicle (UAV) technology, which features high-efficiency reconnaissance and monitoring capabilities, flexible deployment, and multi-functional integration, has become a key driver in the intelligent transformation of modern fisheries. This paper systematically reviews the application of UAVs in critical domains such as resource monitoring and assessment, aquaculture management optimization, and the enhancement of law enforcement and regulatory oversight, while summarizing their technological outcomes and development trajectories. Based on this review, the study identifies major challenges in UAV deployment, including limitations in hardware payload, environmental adaptability, network communication, cost control, ecological impacts, and socio-ethical and privacy concerns. To address these challenges, several optimization strategies are proposed, such as hybrid energy systems that integrate solid-state batteries and solar power, lightweight carbon fiber structures, a "5G plus satellite plus mesh" integrated communication architecture, bioinspired noise reduction techniques, and multi-platform collaborative operations. Looking ahead, the integration of UAVs with artificial intelligence, green materials, and digital twin technologies should be actively promoted to build low-carbon, high-efficiency, and sustainable intelligent UAV systems for smart fisheries. This approach aims to enable the synergistic development of efficient resource utilization and ecological environmental protection.