Development of the Ethogram of Feline Social Interactions (EFSI) to study intraspecific interactions between cats in multicat households

As tension between housecats can have considerable impact on feline and caregiver welfare, gaining insight into the social behaviour within multicat households is valuable. A standard scientific approach to study behaviour in animals involves video-based behavioural observations using an ethogram. We aimed to develop an ethogram of the intraspecific social behaviour of adult cats in multicat households. The development of the ethogram included (a) selection of behavioural elements relevant for the study of feline social behaviour in multicat households and assessment of consensus across experts (face and content validity), and (b) testing intra- and inter-observer reliability when the ethogram is used for video-based behavioural coding. The Ethogram of Feline Social Interactions (EFSI) consists of four behavioural groups, twenty-three behaviours, and three modifier groups which collectively provide descriptions of feline behaviour during social interactions. Results of the itembased reliability analysis between two observers were around or above the 0.8 acceptance threshold for Krippendorff's alpha. Videos are provided online to support other researchers or behavioural professionals in using EFSI. The ethogram is intended to facilitate accurate recording of intraspecific social behaviour by professionals as well as lay people. It is therefore not only useful for studies on sociality in companion cats, but potentially also for monitoring social tension in multicat households by veterinary behaviourists and caregivers.