The elk/moose (Alces alces) was an important resource for prehistoric societies. In prehistoric art, it is often depicted in connection with water. Biologists find that elk spend much time in water and consume considerable amounts of aquatic plants. As freshwater plants can have reservoir ages of hundreds or even thousands of years, there is a risk of a significant reservoir effect in elk bones and antler, and artifacts made of these materials. This pilot study followed several approaches to investigate the possibility of a freshwater reservoir effect in elk. I analyzed modern, historical and archaeological bones and antler from several sites across Eurasia. Skull bone and antler of the same individual were radiocarbon dated, as antler is formed in summer, when the proportion of aquatic diet is supposed to be highest. Age offsets measured in this study were zero to about 500 years. A difference between bone and antler could not be determined. The reservoir effect appears to be smaller than estimated from accounts of elk diet, even in regions where a substantial freshwater reservoir effect is expected. Therefore, the hypothesis of a large proportion of aquatic diet can be rejected for several of the individuals studied here.