Response to Reviewer 1 Comments

SeongIl Baek¹SeungCheol Ji¹Jeong-Hyeon Cho^1,2*

• ¹Jeju Fisheries Research Institute, National Institute of Fisheries Science (NIFS), Jeju-do, Republic of Korea
• ²Mokpo National University, Muan, Republic of Korea

The MS monitored reproductive characteristics of chub mackerel broodstock maintained in a landbased tank under natural temperature and photoperiod conditions for 12 months, providing critical data for optimizing broodstock management and establishing reliable spawning strategies essential for this species. Here are some comments on the manuscript, authors would need to revise accordingly.[Authors' response] We sincerely thank Reviewer#1 for their efforts toward improving the quality of our manuscript through their thoughtful comments and suggestions. We have carefully considered each of the comments below and made the necessary changes in our manuscript. Changes are tracked in the attached manuscript, and the revised sections are highlighted in yellow. We have responded individually to each comment below in red colored text.[Authors' response] We have carefully reviewed and corrected the numbering of figures throughout the manuscript.[Comment 6] Line 361, Could the author give some explanation or speculation here.We have provided a clearer explanation regarding the delayed spawning observed under controlled aquaculture conditions. Specifically, potential factors such as stress as a result of confinement, differences in diet, altered photoperiod and temperature regimes, and limited environmental stimuli compared to wild habitats are likely contributors to delayed spawning. Chronic stress, in particular, has been extensively documented to be a cause of reproductive delays in fish (Pankhurst, 2016;Campbell et al., 1994). Additionally, aquaculture conditions lacking complex environmental cues might affect hormone regulation involved in reproductive readiness, thereby influencing the timing of spawning events (Zupa et al., 2017;Okuzawa and Gen, 2013).