He died at Acre in 1271, while on crusade. According to material in the "Chronicle" of John of Fordun, he had been a participant in the Eighth Crusade. He had been one of a small Scottish contingent that attacked Tunis in 1270, where fellow-Scot and fellow-MacDuff David, Earl of Atholl died. Adam survived, and withdrew with the rest to winter in Sicily. The following spring the contingent joined with the army of Lord Edward and proceeded to Acre, where Adam was taken by disease.