INDEXES OF CONDITION FOR SMALL MAMMALS

Estimates of body condition in mammals may be constructed from measure s of skeletal size and body mass. We illustrate the methodology for do ing this using data from two populations of feral house mice (Mus dome sticus) in Australia, and point out an erroneous method that has commo nly been used in the literature. Indices of condition for individual h ouse mice were not correlated with the fat content of their carcasses. Indices of condition for house mice have a relatively low repeatabili ty because of variation from day to day in body mass and because of va riation in length measurements taken by different observers. Bias in m easurements among observers must be eliminated to make indices of cond ition from live animals useful.