INTRO: Abstract describes a work on relative importance of the effects of genetic domestication and unnatural environment on adaptive behaviour of reared atlantic salmon after release to the wild and its underlying neuroanatomic mechanisms. Authors found out that adaptive post-release behaviour in the wild is selected against in captivity and further dumbed by unnatural rearing environment. This seems to be related to braind development.
MERITS: Work seems to be the first study showing that using wild parents and a novel naturalized rearing method promoted brain growth and therefore individual fitness.
CRITIQUE: I can't see any weaknesses
DISCUSSION: Work has important implications for conservation of species which are raised in captivity and later released in to the wild.
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INTRO: Authors investigate the effect of the domestication of Atlantic salmon on its adaptative behaviour. They find that adaptative behaviour is negatively affected by domestication. They propose a novel method to rear Atlantic salmon, leading to very promising results as the brain growth is enhanced. As a matter of fact, salmons raised with this method show better foraging performances. This study bears promising results for future conservation and captive breeding programs.
MERITS: The abstract exposes the background of the topic pretty well. It also highlights the importance of the work and discuss some previous research done on the subject. It exposes the novelty and the application of the results and does a good job of showing how these results can be implemented into conservation efforts.
CRITIQUE: The abstract is a bit confusing as the sentences are fairly long and somehow complicated to understand. I had to read some of them several times to get the authors point. Some improvement of the general flow of the abstract would be necessary.
DISCUSSION: As captive breeding programs are economically very important, this study shows great potential to tackle important problematics raised by these programs. The results seem very intereseting and are highly relevant for management purposes. Conservation efforts can greatly be improved thanks to this type of study and thanks to these findings.
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INTRO: The abstract shows that standard hatchery rearing and long history of captive breeding in Atlantic salmon decrease brain size with the result of decreased foraging success in the wild with assumed negative fitness implications.
MERITS: The abstract claims that this work is the first to study brain size response to enriched rearing, but this is not true. Näslund et al. has published this in salmon already in 2012: http://www.nrcresearchpress.com/doi/abs/10.1139/f2012-074#.WoKboudpFaQ. The result that wild parents produce offspring with larger brains is novel and a clear merit for this work.
CRITIQUE: General problem in this kind of studies is the lack of direct link of the studied behaviours on fitness. It is not either known how large the domestication effects are at genome or gene expression level. Brain size is a very rough measure and shown to be plastic too (see the above mentioned Näslund et al. 2012 work).
DISCUSSION: This work is to be seen as the first step towards further understanding of the topic, and there is no way to improve the design at this point. The work is valuable as it stands.
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INTRO: This abstract describes an issue of common practice to rear endangered fish species in captivity for stocking purposes. Even though it is widely known that hatchery-reared individuals suffer low post-stocking survival, reasons behing this phenomenon are not yet fully revealed. They have tackled this issue by studying adaptive behaviour of fish and the effects of hatchery-selection to behaviour but also to brain development. Standard hatchery-rearing seems to affect post-stocking behaviour due to decreased brain size. As they propose, negative effects of hatchery-rearing can be reduced by using "naturalized" rearing methods.This abstract describes an issue of common practice to rear endangered fish species in captivity for stocking purposes. Even though it is widely known that hatchery-reared individuals suffer low post-stocking survival, reasons behing this phenomenon are not yet fully revealed. They have tackled this issue by studying adaptive behaviour of fish and the effects of hatchery-selection to behaviour but also to brain development. Standard hatchery-rearing seems to affect post-stocking behaviour due to decreased brain size. As they propose, negative effects of hatchery-rearing can be reduced by using "naturalized" rearing methods.
MERITS: In this abstract, they propose very promising results of reducing post-releasing mortality by using naturalized rearing methods when endangered fish species are reared for restoration purposes. They suggest causality between brain size and behaviour and how used "standard" rearing methods affect brain size negatively leading to lack of behavioural adaptitions. Their findings are not only important for fisheries restoration but also interesting in behavioural evolutionary perspective.
CRITIQUE: I would like to see the measured behaviour introduced here briefly. Now it's coming only in the end that they are talking about foraging behaviour as an adaptive behavioural trait, if I got it right. It is not fully clear to me, how the variation in brain development has been observed here so I am not able to comment much the methodological details. It would be convenient to provide a substantial information about the difference of brain development between hatchery and "naturalized" rearing (i.e. effect sizes). I found the term "naturalized" slightly hard to understand whether it means sort of an enrichment to the standard rearing method or something completely different. Brief introduction to this method would be an improvement to this abstact.
DISCUSSION: I found utmost importance of this abstract in revealing causality in brain development, foraging behaviour and hatchery-rearing practices. This study has a strong potential to benefit species re-introduction programs and it is a valuable addition to the increasing amount of knowledge of behavioural conservation. The role of behavioural variation and adaptations in general has been disregarded in conservation programs and it has been brought only recently to the serious debate. I hope this study among the others will bring up the importance of the role of behaviour in species conservation and hopefully will lead to action.