Fig. 7. Differences between observed and theoretical fatty acid composition of lipid reserves NL in fat semipalmated sandpipers. Theoretical values were calculated from measured compositions in lean birds and in the Corophium diet, assuming that dietary fatty acids are stored without modifying chain length or number of double bonds. In this comparison, stored fatty acids with a higher observed abundance than expected have a positive value whereas those with a lower abundance have a negative value. Values are means ± s.e.m. (N=13).