Life-history parameters of adult females of Merluccius capensis (Gadidae) off the south coast of South Africa.

This study explores the life-history parameters of female Merluccius capensis off South Africa (N = 1819) during 2014-2016, including gonadosomatic index (GSI), length-at-maturity, length-weight relationships, and condition indices (relative condition [k] and Fulton's condition factor [K]). We detected weak indications of two peaks of spawning within the year, the first in austral autumn from March to May, whereas the other in austral spring around August. GSI was slightly higher in spring and autumn, though still low at all maturity stages (≤7%), though the opposite was true for the actively spawning stage (≥7%) as well as access to less such data during winter- and summertime.

Spawning fish maintains trophic synchrony across time and space beyond thermal drivers.

Increasing ocean temperature will speed up physiological rates of ectotherms. In fish, this is suggested to cause earlier spawning due to faster oocyte growth rates. Over time, this could cause spawning time to become decoupled from the timing of offspring food resources, a phenomenon referred to as trophic asynchrony.

Increasing temperature and prey availability affect the growth and swimming kinematics of Atlantic herring () larvae.

Climate change will increase the magnitude and duration of warming events and the variability in the phenology and abundance of available prey to the early life stages of fish. These factors influence physiological, behavioral and ecological processes, impacting growth, development and survival. Using a fully factorial design with two prey-availability treatments (1200 prey items L (high prey abundance) or 40 prey items L (low prey abundance)) under three temperature regimes (8, 10 and 12°C), the swimming kinematics of 6-week old spring-spawning Atlantic herring larvae were examined using silhouette video photography.

Tracking oocyte development and the timing of skipped spawning for north-east Arctic haddock (Melanogrammus aeglefinus).

The present study tracked oocyte development over 9 months and noted incidences of 'skipping', i.e., adults terminating their upcoming reproductive cycle, in field-caught north-east Arctic (NEA) haddock (Melanogrammus aeglefinus), currently the largest stock of this species.

First thorough assessment of de novo oocyte recruitment in a teleost serial spawner, the Northeast Atlantic mackerel (Scomber scombrus) case.

The understanding of teleost fecundity type (determinate or indeterminate) is essential when deciding which egg production method should be applied to ultimately estimate spawning stock biomass. The fecundity type is, however, unknown or controversial for several commercial stocks, including the Northeast Atlantic mackerel (Scomber scombrus). Aiming at solving this problem, we applied state-of-the-art laboratory methods to document the mackerel fecundity type, including any de novo oocyte recruitment during spawning.