A series of measurements (lengths, circumferences, skinfolds, masses and re
sistance) was taken on 29 red foxes (Vulpes vulpes) of both sexes before an
d after their death during the autumns of 1994 and 1995. Body composition o
f each carcass was determined by chemical analysis of homogenized samples o
f viscera, carcass and skin. Eight multiple regression models were then dev
eloped to predict body water, fat, protein, and mineral mass using body mea
surements as independent variables taken on live or dead animals. All final
models were highly significant (P < 0.0001) and included three or four exp
lanatory variables. Adjusted coefficients of determination varied between 0
.95 for water mass and 0.81 for mineral mass. The models cover a wide range
of conditions as percent body fat in the 29 samples varied between 1.1 and
28.4%. Our models can serve for management or research purposes with live
or dead red foxes as they are quick, inexpensive and nondestructive.