The condition of the ovaries in juvenile fall- and summer-run chum salmon prior to release was studied at five fish hatcheries that operate on Sakhalin Island. It has been found that juveniles released from different hatcheries, while having a similar body weight, may differ in the degree of development of their ovaries. Juvenile summer-run chum salmon showed a lower oogenesis rate at the hatchery with the warmest water and a higher oogenesis rate at the relatively cold-water hatcheries, compared to that of fall-run juveniles.
Kolomytsev, V. S., Lapshina, A. E., & Зеленников, О. В. (2018). THE CONDITION OF OVARIES IN HATCHERY-REARED JUVENILE SUMMER- AND FALL-RUN CHUM SALMON, ONCORHYNCHUS KETA (WALBAUM, 1792), IN SAKHALIN OBLAST. Russian Journal of Marine Biology, 44(1), 36-41. https://doi.org/10.1134/S1063074018010066