Objectives: The main objective of the study was to collect and rear unmarketable, small sized S.javus which is mostly rejected by traditional fisherman. During fishing activities, under ranging in sizes from 25 40 kg (< 30-40 % total catch/day) being captured. Due very low marketable value these fishes (<250 g) get rejected. Therefore, we utilized this as an economically viable option for...

Harvesting wild populations may contrast or reinforce natural agents of selection and potentially cause evolutionary changes in life-history traits such as growth and maturation. Harvest selection may also act on behavioral traits, although this field of research has so far received less attention. We used acoustic tags and a network of receivers to monitor the behavior and fate of individual A...

Identifying the most sensitive indicators to changes in fishing pressure is important for accurately detecting impacts. Biomass is thought to be more sensitive than abundance and length, while the wariness of fishes is emerging as a new metric. Periodically harvested closures (PHCs) that involve the opening and closing of an area to fishing are the most common form of fisheries management in th...

This paper formulates a simple biomass growth model of a fishery. The property rights regime is of the unregulated local common property type with a fixed number of fishermen and where the fish stock is exploited in a myopic profit-maximizing manner. Within this resource management setting it is demonstrated that more modern fishing technology has a two-sided profitability effect, and where the...

This paper develops a sustainable yield harvesting model for the wild Atlantic salmon (Salmo salar), where the population comprises different age classes. It is shown that the weight– fecundity relationship of the spawning population, comprising young and old fish, is crucial for the maximum sustainable yield fishing composition. First, the optimal harvest is found when fecundity is approximate...

Public concern over biodiversity loss is often rationalized as a threat to ecosystem functioning, but biodiversity-ecosystem functioning (BEF) relations are hard to empirically quantify at large scales. We use a realistic marine food-web model, resolving species over five trophic levels, to study how total fish production changes with species richness. This complex model predicts that BEF relat...

A stochastic optimization model for management of aquacultured fish for sale and ecological education is established. Population dynamics of the fish is described with a system of stochastic differential equations assuming that they are stochastically harvested after an opening time: the variable to be optimized. A remarkable difference between the present and conventional models for the aquacu...

The potential of microalgae biomass production for low-cost commodities—biofuels and animal feeds—using sunlight and CO2 is reviewed. Microalgae are currently cultivated in relatively small-scale systems, mainly for high value human nutritional products. For commodities, production costs must be decreased by an order of magnitude, and high productivity algal strains must be developed that can b...

The quantity and quality of propagules, i.e. reproductive output, play a key role in the dynamics of exploited populations, with particular implications for sex-changing fish. �ere, we studied for the first time the effects of maternal traits on the reproductive output of the Mediterranean rainbow wrasse Coris julis, a sequential hermaphroditic fish widely distributed in temperate marine coasta...