Two is not company -- as far as fish are concerned

June 29, 2009

Research at the Universities of Plymouth and Exeter has shown that fish kept alone or in small groups are more aggressive and exhibit fewer natural behaviors such as shoaling. Dr Katherine Sloman will discuss the findings and their implications for welfare guidelines for aquarium fish at the Society for Experimental Biology meeting on Monday June 29.

It might be assumed that aquarium fish don't mind who or what they encounter in their tanks from one minute to the next, if their famously (but incorrectly) short memory is to be believed. Scientists at the Universities of Plymouth and Exeter have carried out research to show this is not the case and are striving to improve conditions for keeping fish in home aquaria.

In line with the aim to establish welfare guidelines for fish, these researchers have been collaborating with the WALTHAM Centre for Pet Nutrition, examining healthy stocking densities and the use of novel objects with fish commonly kept in home aquaria. This current research, to be presented on Monday 29th June 2009 at the Society for Experimental Biology Meeting in Glasgow, looked at two common aquaria species, neon tetras and white cloud mountain minnows. As Dr Katherine Sloman from the University of Plymouth explains 'fish kept alone or in pairs show higher levels of aggression than those kept in groups of ten or more; large groups are also more likely to exhibit natural behaviours such as shoaling'.

Further research is needed to ascertain the criteria for fish welfare in home aquaria; the results of these studies, funded by the WALTHAM Centre for Pet Nutrition, should go some way to improving welfare for these environmentally, economically and socially important and interesting animals.

Source: Society for Experimental Biology