Survival of European Mouflon (Artiodactyla: Bovidae) in Hawai'i Based on Tooth Cementum Lines

Reliable techniques for estimating age of ungulates are necessary to determine population parameters such as age structure and survival. Techniques that rely on dentition, horn, and facial patterns have limited utility for European mouflon sheep (Ovis gmelini musimon), but tooth cementum lines may offer a useful alternative. Cementum lines may not be reliable outside temperate regions, however, because lack of seasonality in diet may affect annulus formation. We evaluated the utility of tooth cementum lines for estimating age of mouflon in Hawai'i in comparison to dentition. Cementum lines were present in mouflon from Mauna Loa, island of Hawai'i, but were less distinct than in North American sheep. The two age-estimation methods provided similar estimates for individuals aged ≤3 yr by dentition (the maximum age estimable by dentition), with exact matches in 51% (18/35) of individuals, and an average difference of 0.8 yr (range 0–4). Estimates of age from cementum lines were higher than those fr...