Tooth Wear as a Mortality Factor in the Weddell Seal, Leptonychotes Weddelli

A simple method for etching and staining macrosections of Weddell seal (Leptonychotes weddelli) canine teeth for aging by counting dentinal annuli is described. Weddell seals abrade sea ice with their teeth to maintain breathing holes during winter. This results in the tooth wearing away to the pulp cavity and subsequent infection and abscessing. An arbitrary scale was devised to measure dental wear and necrosis on 171 Weddell seal skulls for which age had been determined. An index of tooth wear and necrosis showed little change up to the average age of 8 to 9 years, followed by a marked increase in subsequent years indicating a correlation between tooth condition and mortality of adults.