– Decision tables provide a simple and systematic summary of the consequences of alternative management policies or decisions given various possible true, but generally unknown, states of nature. Decision tables are especially useful for evaluating the precautionary properties of those decisions, as they require explicit consideration of a variety of “what if” possibilities, some of which could...

13 We update recent work on the scientific inference and reproductive biology of steepness in three 14 directions. First, we show how variation in natural mortality can be included in the formula 15 for steepness, for both a biomass dynamics and age-structure models. We do this using the 16 delta-method, so that only the mean and covariance of natural mortality rates appear in the 17 characteri...

Sperm limitation is widespread across many animal species. Several mechanisms of sperm allocation have been proposed, including optimal allocation according to clutch size and equal allocation across females. However, considerably less effort has been directed at investigating the behavioural signals associated with sperm limitation in males, which may include mating rate and the intensity of c...

Management of marine species often relies on biological reference points (BRPs): threshold and target indicators that trigger management actions. These BRPs are usually based the biology rarely consider environmental effects. Under climate change, this is problematic as many biological/physiological relationships assumed temporally static. This spurious assumption can lead to inaccurate practic...

Abstract Catches have remained relatively high in the Gulf of Thailand and Bohai Sea, China, despite severe biomass declines (around 95%) evidenced by fishery-independent surveys. Such production at very low stock sizes is not predicted simple-surplus theory, but can be explained age-structured models that predict recruitment rates even when per recruit (BPR) has been drastically reduced. Recru...

This study investigated the effects of mate switching on the reproductive performance of the severum cichlid, Herosseverus, by advancing the egg and larval production in hatcheries. Two reproductive tactic treatments of “monogamous pair” and “mate switching” were used for evaluating 4 reproductive traits of egg production, hatching rate, spawning intervals, and starvation tolerance of the larva...

This study investigated the effects of mate switching on the reproductive performance of the severum cichlid, Herosseverus, by advancing the egg and larval production in hatcheries. Two reproductive tactic treatments of “monogamous pair” and “mate switching” were used for evaluating 4 reproductive traits of egg production, hatching rate, spawning intervals, and starvation tolerance of the larva...

Changes in geographical location of spawning and/or in spatial abundance of spawners may influence offspring survival. In Iceland, the spatial dynamics of spawning cod (Gadus morhua L.) are complicated due to unequal distribution of size classes on the main spawning grounds. Information on abundance, age, and size distributions during peak spawning, potential fecundity, egg size, and estimated ...

This study investigates the effects of dietary lipid sources on the growth and reproductive performance of Nile tilapia over three consecutive spawnings. Fish were reared using three experimental diets, with the goal of replacing dietary fish oil with palm oil. Three experimental diets and a commercial   trout diet was used as the control. The effect of dietary lipid on the growth performance, ...