First Observations of Potential Iteroparity in Pacific Capelin Mallotus catervarius Aquaculture, Fish and Fisheries

Using histology to examine ovarian structures in Pacific capelin for the first time, we found biological evidence that captive, age-1, female Pacific capelin Mallotus catervarius are capable of iteroparity (41% of mature females). Evidence of the potential to spawn over multiple years included more than one oocyte cohort, including primary growth and vitellogenic oocytes in maturing fish, or primary growth and post ovulatory follicles in spent fish.The data on iteroparity rates provide a better understanding of how fish might respond to variable or extreme environments, as a population with mixed or flexible parities may have more flexibility in spawning frequency, reproductive output, and survival.