IN recent times there has been a concerted push by animal rights activists and a small group of fish behaviour scientists to try and show that fish are conscious, sentient beings, so as to affect changes to fisheries and fish use worldwide. One of the pillars of this belief was a paper published in 2015 by Rey et al. in the Journal of Experimental Biology where the authors alleged that fish exhibited “emotional fever” through allegedly exhibiting a preference for warmer water after being handled in a net. The study and its controversial claims for evidence of emotions and consciousness in fish received world-wide media coverage at the time. Despite observations by other scientists that the original study was flawed, the claim that fish experience “emotional fever” has been used by some pro fish sentience scientists and fish welfare activists as sufficient evidence to begin campaigns that call for an end to a variety of fishing practices.
However, a new article published in the same journal by researchers at the University of St Andrews in the UK has found the original study was fatally flawed. After first conducting a “null distribution” test that considered fish behaviour in the absence of thermal variation (an important control that was not performed in the original study), the new research found not only was there no evidence of preference for “fever” after netting, instead they found a temporary preference for lower water temperatures. In conclusion the scientists stated “We observed no evidence for stress induced hyperthermia; across two experiments the stressed fish showed no preference for warmer areas”. This is a stunning blow to the “pro fish sentience” crowd, who have been increasingly active in their campaigns against fishing in recent times. It will be interesting to see if this new study receives as much media publicity as the now disproved and disgraced original.
The new article entitled “ No experimental evidence of stress-induced hyperthermia in zebrafish” can be found HERE.
The Conversation also published this document about the original study, which now contains discredited information.
