New research has shown that goldfish can remember pain for at least a day, shattering the widespread misconception that these fish have a three-second memory span yet again.
Peter Laming, Sarah Millsopp and Rebecca Dunlop of the Queen's University in Belfast are to publish the results of a new study in the journal Applied Animal Behaviour Science which says that goldfish can learn to avoid parts of their tank in which they receive electric shocks for at least 24 hours.
Trout showed similar responses to the shocks, but strayed into the areas in which shocks were administered more frequently than goldfish.
Dunlop told The Telegraph: "Angling is not considered to be a cruel sport as it has been assumed that fish cannot perceive pain. Rather it is a reflex action.
"This paper shows that pain avoidance in fish does not seem to be a reflex response, rather one that is learned, remembered and is changed according to different circumstances. Therefore, if fish can perceive pain, then angling cannot be continued to be considered a non-cruel sport."
The findings are expected to reopen the debate about whether angling is a cruel sport.
NociceptionPrevious work by Dunlop and Laming has looked at pain detection, or nociception, in both trout and goldfish. In these studies the scientists used a "pin-prod" stimulus rather than electric shocks.
Similarly, this study also showed differences in pain perception by trout and goldfish.
For more details see: Dunlop R, Laming P (2005) - Mechanoreceptive and nociceptive responses in the central nervous system of goldfish (Carassius auratus) and trout (Oncorhynchus mykiss). J Pain. 2005 Sep;6(9):561-8.