The North Atlantic Marine Mammal Commission

Contact

Upcoming events:

NAMMCO 25

Report of the 19th Meeting of the NAMMCO Scientific Committee

The 19th meeting of Scientific Committee was held in Tasiilaq, East Greenland, 19 – 22 April 2012. The report has been published in the 2012 Annual Report.

Report of the Workshop on Age Estimation in Monodontids

The Workshop on Age Estimation in Monodontids was held in Tampa, Florida, US, 26-27 November 2011. The workshop was in response to a direct request by the Scientific Joint Working Group of NAMMCO and the JCNB (Joint Canada-Greenland Committee on Narwhal and Beluga). The workshop focused on aging methods in beluga and narwhal, but also embraced aging methods in other marine mammal groups, and new technology that is proving promising.


Beluga tooth

The workshop report lists a number of conclusions, including the acceptance of one Growth Layer Group (GLG) deposition annually in beluga teeth. Recommendations include suitable methods of aging for monodontids, including dentine GLG in beluga, aspartic acid racemisation (AAR) of eye lens nucleus in narwhal, and monitoring free-living belugas for later validation of longevity and reproductive age parameters. The use of reference collections of beluga teeth and tooth images, especially for known-age and -history animals, for standardisation of GLG counting within and among laboratories is essential, and frequent testing of accuracy and precision in GLG counting is important for maintaining standards.