Intraspecific behavioural interactions in Apodemus microps: a peaceful mouse?

Social interactions of captive Apodemus microps Kratochvil et Rosicky, 1952 were studied in dyadic encounters. In neutral-cage conditions both sexes s howed exceptionally high proportion of amicable behaviour ton average ca 30 % of the total time) and very low proportion of agonistic behaviour (up to 2.1%), when compared to patterns reported in other Apodemus species. The hi gh share of amicable behaviour cannot be simply explained by decreased aggr ession. Mice actively offered amicable acts to their unfamiliar conspecific s even during the short-time (ten-minute) encounters. This phenomenon may b e interpreted as a cooperative strategy. However, the near absence of aggre ssion in A. microps could be altered by specific social contexts: males, bu t not females, became mutually agonistic when tested in a home-cage or in t he presence of a female.