1 Natural History Museum of Denmark, Faculty of Science, Københavns Universitet2 Department of Mathematical Sciences, Faculty of Science, Københavns Universitet3 Pharmaceutical Design and Drug Delivery, Department of Pharmacy, Faculty of Health and Medical Sciences, Københavns Universitet4 Center for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen,5 Greenland Institute of Natural Resources6 Age Dynamics, Kongens Lyngby, Denmark7 Icelandic Meteorological Office, Reykjavík, Iceland8 Department of Pharmacy, Faculty of Pharmaceutical Sciences, Københavns Universitet9 Natural History Museum of Denmark, Faculty of Science, Københavns Universitet10 Department of Mathematical Sciences, Faculty of Science, Københavns Universitet11 Department of Pharmacy, Faculty of Pharmaceutical Sciences, Københavns Universitet
Eyeballs from 121 fin whales (Balaenoptera physalus) and 83 harbor porpoises (Phocoena phocoena) were used for age estimation using the aspartic acid racemization (AAR) technique. The racemization rate (kAsp) for fin whales was established from 15 fetuses (age 0) and 15 adult whales where age was estimated by reading growth layer groups (GLGs) in the earplugs. The (kAsp) for harbor porpoises was derived from 15 porpoises (two calves and 13 > 1 yr old) age-estimated by counting GLGs in the teeth and two calves classified to age based on length. The (kAsp) values were estimated by regression of GLGs against D/L ratios. For the fin whales an (kAsp) of 1.15 × 10−3/yr (SE ± 0.00005) and a D/L ratio at birth [(D/L)0] of 0.028 (SE ± 0.0012) were estimated, which is in agreement with rates for other mysticeti. For the harbor porpoises a (kAsp) of 3.10 × 10−3/yr (SE ± 0.0004) and a (D/L)0 value of 0.023 (SE ± 0.0018) were estimated, which is considerably higher than found for other cetaceans. Correlation between chosen age estimates from AAR and GLG counts indicated that AAR might be an alternative method for estimating age in marine mammals.