Conclusions: Aquaculture and Behaviour

Abstract

This chapter draws together the information presented earlier in the book. Firstly, the criteria that must be met if aquaculture is to be effective and sustainable are discussed and summarised. Second, the reader is reminded that cultured fish show a broadly similar repertoire of behaviour to that of their wild counterparts, in spite of striking differences between the conditions prevailing in fish farms and in nature. A general account is then given of the problems that can arise from the expression of natural behaviour by fish in production systems. Such problems may come from the mechanisms that control behaviour, from the way in which it develops and from the fact that behaviour is the product of natural selection favouring traits that promote Darwinian fitness. By the same token, solutions can be found to such problems based on an understanding of these different aspects of fish behaviour and these are exemplified with reference to examples given in Chapters 4-10. Up to this point, attention has been focused on aquaculture as currently practised, but the final section looks to the future, attempting to anticipate how fish culture might change. Likely developments include diversification of culture species, increased intensification of aquaculture systems, greater use of genetic technologies for stock improvement, increased emphasis on environmental protection and fish welfare and increasing overlap with commercial fisheries, through capture-based aquaculture, and with conservation, through recruitment enhancement. In each case, the part that behavioural biology might play in influencing such developments is discussed.

Aggressive and cannibalistic behavior of African catfish larvae: effect of different doses of methyltestosteron injecting to female broodstock and larval stocking densities

“…Zairin et al (1992) explained that the testosterone content in C. batrachus increased in the 8 th month along with the vitellogenesis process and gonad maturation. Mehta & Beer (2009), Huntingfold et al (2012), and Nakamura (2013) also stated that testosterone is not only stored in the embryo of the egg but also the egg yolk and it keeps increasing along with the larvae development.…”

“…The blood profile is commonly analyzed to evaluate physiology responses caused by adaptation towards environmental changes. Huntingfold et al (2012), Nardocci et al (2014), and Yarahmadi et al (2015) added that generally there are three types of physiology responses, i.e. primary, secondary, and tertiary response.…”

Different Wavelengths of Light Have No Effect on Zebrafish Fecundity

“…The intensity of light as it hits the surface of water varies by the time of day and seasons. At dawn, sunlight hits the water surface at a low angle and from a long atmospheric path, resulting in a reduced intensity and shorter wavelengths [25]. Additionally, the rainy monsoon season is rich in UV and blue light [26].…”

Effects of Domestication on Fish Behaviour

“…In his book, Jensen [7] described the effects of domestication in vertebrates, mainly on birds and mammals but there was nothing on fishes. Before that, there were three major reviews [3,4,8] on the influence of aquaculture and domestication on fish behaviour. In these papers, the authors summarised most of the available information on the effects of domestication on different traits of fish behaviour.…”