Gills Just Want to Have Fun: Can Fish Play Games, Just like Us?

Abstract

It is common to observe play in dogs, cats, and birds, but have we been ignoring play in one of the most common house pets of all… fish? Aquarium fish are often used as meditative decoration in family households, but it could be that fish have similarly diverse behavioral repertoires as mammals and birds. To examine this theory, we conducted field tests at local pet stores where a range of aquarium fish species was tested for responsiveness to laser pointer stimuli. Out of 66 species of fish tested, over 80% showed a tendency to be interested in the moving laser spots, particularly red ones. Whether this behavior constitutes play is an active topic of investigation that we examine in this work.

Point for Enrichment, Point for Welfare—Testing Use of a Laser Pointer with Arapaima gigas

“…The current literature on this species is limited to publications regarding its biology and farming. In line with the recent findings of other fish species’ response to the use of a laser pointer [ 13 ], our arapaimas’ response could be categorised as moderate or even high.…”

“…The laser pointer enrichments also enhanced activities, as indicated by increased travelling, layer changes, and physical contact during test sessions. Adequate environmental enrichments have been documented to increase exploratory behaviour in steelhead ( Oncorhynchus mykiss , [ 17 ]), prompted attentiveness/tracking, chasing, and catching in fish [ 13 ], and increased activity is generally accepted as a positive welfare indicator [ 48 ]. Thus, the documented increased travelling further supports the positive effect of the laser pointer.…”

“…Their detailed ethogram included 36 different behaviours that were classified into five categories such as aggressive, social, maintenance, reproductive, and submissive [ 10 ]. Ethograms have also been adapted to investigate social plasticity [ 11 ], genotype-environment interaction [ 12 ], play behaviour [ 13 ], or even behavioural responses to interactive robots [ 14 , 15 ].…”

“…However, in a recent study, 66 fish species were exposed to a laser pointer. It was found that the majority of the fish showed at least a moderate level of interest in the stimuli [ 13 ].…”