Influence of climate oscillations on dentinal deposition in teeth of Commerson's dolphin

DELLABIANCA, N. A.; HOHN, A. A.; GOODALL, R. N. P.; POUSA, J.; MACLEOD, C.; LIMA, M.

GLOBAL CHANGE BIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2012 vol. 18 p. 2477 - 2486

1354-1013

Effects of climate oscillations on populations in marine environments are produced mainly through the lower trophic levels. Marine mammals, as top predators, are affected indirectly by these fluctuations, showing variations in their survival, growth and reproduction. We evaluated whether we could detect climate effects on Commerson?s dolphin, Cephalorhynchus commersonii, in subantarctic waters. For this, we tested the effects of the Southern Annular Mode (SAM) and El Niño Southern Oscillation (ENSO) events and mean annual sea surface temperature (SST) on anomalies in dentine from 1960 to 2005. Then, growth parameters between animals with a normal dentine deposition patterns and those with an anomalous dentine pattern were compared. The presence of anomalous dentine was related to the SAM, increasing in frequency with negative values of the SAM. No relationship was found among dentinal anomalies, the ENSO and SST. There were no significant differences in growth parameters between animals with dentinal anomalies and those with a normal deposition pattern. These results suggest that climate effects might be apparent using characteristics in teeth inasmuch as teeth serve as permanent recording structures.