Fish Reproduction in a Changing World: Physiology, Conservation and Stressors

Reproduction forms the foundation for the sustainability of fish populations, driving both the productivity of global aquaculture and the conservation of aquatic biodiversity. In fish, reproductive success depends on a series of intricate, closely regulated processes, including the neuroendocrine control of the hypothalamic–pituitary–gonadal (HPG) axis, gametogenesis, maturation, spawning behavior, fertilization, and embryonic development. These processes are uniquely sensitive to environmental cues, rendering fish highly vulnerable to rapid physical, chemical, and sensory changes in their surroundings. Recent evidence highlights how rising temperatures, increased frequency of marine heatwaves, ocean acidification, altered salinity and water flow, and habitat modifications disrupt reproductive timing and physiological signaling. Furthermore, mounting exposure to complex pollutant mixtures—including endocrine-disrupting chemicals (EDCs), PFAS, pharmaceuticals, pesticides, and micro- and nanoplastics—alongside chronic stressors such as noise and artificial light, threatens to reduce gamete quality, fertility, and offspring fitness. The expanding scope of aquaculture adds both stress and opportunity, underscoring the urgent need to optimize reproductive management while considering animal welfare and system resilience.Amidst these converging challenges, fish reproductive biology faces a critical juncture. Persistent environmental and anthropogenic pressures threaten wild populations, aquaculture stability, and biodiversity preservation. The complex and often interacting stressors involved can cause reproductive failures that are difficult to diagnose, compare across taxa, or translate into actionable management and hatchery strategies. This Research Topic seeks to bridge these knowledge gaps by inviting mechanistic and applied studies that connect the dynamics of wild and cultured systems. The goal is to clarify the effects of environmental and human-induced stressors on reproductive outcomes, highlight innovative approaches to improve aquaculture reproductive performance, and accelerate the development and application of scalable cryopreservation techniques crucial for both production and conservation. Through rigorous and transparent experimental designs, we aim to generate actionable insights that advance science, inform policy, and enhance management and hatchery practices.This Research Topic encompasses mechanistic, environmental, and applied research on fish reproduction across wild and aquaculture contexts, with a special focus on environmental threats and innovative solutions. Research not directly linked to reproductive processes or their intersection with environmental or anthropogenic factors falls outside the scope of this topic. We welcome submissions addressing, but not limited to, the following themes:i) Reproductive physiology: HPG-axis regulation, endocrine signaling, gametogenesis, and fertilizationii) Impacts of anthropogenic and environmental stressors: temperature rise, hypoxia, acidification, salinity and flow changes, multi-class contaminant mixtures (EDCs, PFAS, pesticides, pharmaceuticals, metals), micro/nanoplastics, noise, and light pollutioniii) Biomarkers, adverse outcome pathways (AOPs), epigenetics, and transgenerational effectsiv) Biotechnologies for aquaculture: spawning control, broodstock nutrition and welfare, genomics, phenotyping, gene editing, hatchery and recirculating aquaculture system (RAS) optimization, and decision supportv) Conservation strategies: genetic management, supportive breeding, assisted reproduction, policy, and ethicsvi) Cryopreservation and biobanking: protocol development, quality control and assurance, and FAIR data managementAppendix: Manuscript types may include Original Research, Methods and Protocols, Brief Research Reports, Reviews, and Mini Reviews. Topic editors: Amin Sayyari, Rafael Henrique Nóbrega Source: https://www.frontiersin.org/research-topics/72420/fish-reproduction-in-a-changing-world-physiology-conservation-and-stressors