In recent years humans have begun to focus on exploration of the sustainable management of fisheries and aquatic ecosystems which relies heavily on advanced techniques for fish size estimation, bycatch reduction, and fish counting. These interconnected areas play a pivotal role in ensuring the health of fish populations, conserving biodiversity, and supporting the economic viability of fisheries. Technologies like sonar, AI, and underwater imaging have drastically changed the traditional methods for monitoring growth systems in aquacultures, fishing development, and even growth pattern assessments. Size estimation in fish catches is highly important in creating catch quotas and regulation. To improve the capture of target species while reducing capture of bycatch, these selective fishing mechanics, behavioral techniques, and real-time monitoring have proven to be effective both ecologically and legally. Additional modern methods such as automated imaging, e-DNA analysis, and hydro-acoustics technology have aided in counting fish for stock assessments and population control. All these methods cannot be grouped together and claim to be true modern management methods of fisheries. This paper discusses the evolution of aquatic life in a comprehensive way. In the integration of sustainable practices, from the development of modern telecasts, we are able to witness the manual mechanics of forming fisheries. These methods help curb overfishing, climate change, habitat degradation, and put humans and their desires in balance with the underwater ecosystem in order to promote a better future.