Oocyte recruitment and fecundity type in fishes: Refining terms to reflect underlying processes and drivers

Only with new technology and the ability to simulate systems are we beginning to understand fish reproductive processes at the individual scale over time. Traditionally, oocyte recruitment and fecundity type in fishes have been based on a “snapshot” approach, that is a histological micrograph and/or oocyte size frequency distribution of a spawning capable female has been assumed to indicate oocyte recruitment processes over time. This has important implications as the asynchronous and group‐synchronous oocyte recruitment patterns are associated with indeterminate and determinate fecundity types, respectively, and thus affect estimates of reproductive potential and spawning biomass (if using egg production methods). However, a historic review of these terms revealed that they are not applied consistently, with the same oocyte recruitment pattern often assigned to both of these by different scientists. The intent of this study is to develop a conceptual model of oocyte recruitment processes over time, key drivers, and resulting “snapshots” to refine oocyte recruitment terms, definitions, and the methods needed to identify them.