James J NaglerView profile
Professor
James J Nagler is a Professor of Biological Sciences in the College of Science at the University of Idaho, where he directs the Center for Research on Invasive Species and serves as Affiliate Faculty at the Aquaculture Research Institute. His research integrates endocrinology, genetics, and ecology to address critical questions in fish reproduction and invasive species management. His educational background includes a Ph.D. from Memorial University of Newfoundland (1991). Ph.D., Memorial University of Newfoundland, 1991 Nagler's research focuses on reproductive biology of salmonids, particularly examining how photoperiod, diet, contaminants, and energy balance regulate maturation, spawning behavior, and rematuration. His work has established key biomarkers for reproductive status and elucidated endocrine pathways involving growth hormone, insulin-like growth factor-1, and sex steroids. He investigates both wild populations and aquaculture systems, with significant contributions to understanding iteroparity in steelhead trout and precocious maturation in Chinook salmon. Analysis of his recent publications (2017-2025) reveals consistent emphasis on repeat spawning physiology in steelhead, energy allocation trade-offs, genomic approaches to maturation traits, and environmental manipulations for aquaculture management. His work bridges fundamental endocrine mechanisms with applied conservation challenges, particularly regarding invasive species impacts on aquatic ecosystems. As Director of the Center for Research on Invasive Species, Nagler leads interdisciplinary efforts to understand and mitigate invasive species threats, while his affiliation with the Aquaculture Research Institute connects his research to sustainable fish production practices.









