Stereotypy

A repetitive, invariant behaviour pattern with no obvious function, often associated with restrictive housing, frustration, or chronic stress.

In horses, stereotypies include crib-biting (biting the stable door or post and sucking air), weaving (rhythmic side-to-side swaying of the head and shoulders), box-walking (repetitive circling around a stable), and several other patterns. In dogs, stereotypies include tail-chasing, spinning, fly-snapping, and shadow-chasing. In zoo animals, pacing along enclosure boundaries is a particularly common stereotypy. Cats can develop stereotypies including excessive grooming and tail-chasing. The patterns vary by species but the underlying phenomenon is similar.

Stereotypies are typically understood as coping behaviours that develop in environments where the animal cannot perform behaviours that matter to them. The repetitive behaviour appears to provide some form of behavioural regulation in the absence of more functional alternatives. This understanding is supported by the observation that stereotypies tend to develop in restrictive environments and tend to be reduced (though not always eliminated) by enrichment and behavioural opportunity.

Stereotypies are markers of welfare concern even when the immediate cause has been removed. An animal who developed a stereotypy in a restrictive environment may continue the behaviour even after the environment is improved, because the behaviour has been incorporated into their behavioural repertoire and may be self-reinforcing in some way. This is one of the reasons that prevention (avoiding the development of stereotypies) is generally more effective than treatment (trying to eliminate them once established).

The welfare science consensus is that stereotypies indicate the animal has experienced welfare concern at some point, whether or not the immediate cause is still present. The presence of stereotypies in a population (a herd, a kennel, a zoo collection) is treated as a signal that management practices warrant review.

Modern welfare assessment treats stereotypies as one indicator among several, recognising that the absence of stereotypies does not guarantee good welfare and that the presence of stereotypies does not necessarily indicate current poor welfare.