Scientists have finally figured out how to determine the age of a lobster. Brunswick presented his research Thursday at a lobster science conference in Portland, Maine. Raouf Kilada of the University of New Brunswick presented his research Thursday at a lobster science conference in Portland, Maine. Scientists already knew how to tell a fish's age by counting the growth rings found in its inner ear and a scallop or clam's age from the rings of its shell. But nobody knows how old lobsters can live to be. Some people estimate they live to over 100. Before now it was thought that when lobsters, shrimp and crabs molt, they shed all parts of their bodies that might record annual growth bands. Kilada and other researchers found that growth rings are found in a lobster's eyestalk and in teeth-like structures in their stomachs used to grind up food.