Stable isotopes in mammal bones are mainly used to reconstruct dietary preferences and their use as palaeoclimatic indicators is less developed. However, important variations in 15N abundances observed in the bone collagen of large mammals during the Late-glacial and early Holocene have been tentatively linked to a general increase in temperature. In order to test this hypothesis, we analysed nitrogen and oxygen isotopic abundances from bones of red deer (Cervus elaphus) from the Rochedane site (Jura, France). We observe a clear linear relationship between 15N and 18O that demonstrates the effect of temperature on the abundance of 15N in red deer bone collagen. These results suggest that an increase in soil maturation during global warming of the Late-glacial and early Holocene led to an increase of 15N in soils and plants that was passed on to their consumers. Red deer seem to be particularly suited for palaeoclimatic reconstruction based on the isotopic signatures of their bones. Copyright © 2009 John Wiley & Sons, Ltd.