Knowing the age of wild animals is important to understand many aspects of a species’ life history and ecology. Body structures used to determine age can also provide information on an animal’s general health and reproductive history as well as the influence of their environment on growth, health and reproduction.
Techniques using bone and teeth to estimate the age of marine mammals were first developed in the 1950s and continue to be refined and verified for an increasing number of species. The marine mammal collection at the South Australian Museum is the largest and most comprehensive in Australia. It includes many teeth collected from whales, dolphins, porpoises, seals, sea lions and dugongs. The raw materials in this collection and the need for a national facility to study age, provided the impetus to establish a Marine Mammal Ageing Facility in 2007. Financial assistance was provided by the Australian Marine Mammal Centre (Australian Antarctic Division, Hobart).
The Facility is managed by Dr Catherine Kemper (Senior Research Scientist, Mammals, South Australian Museum) with the assistance of Dr Karen Evans (CSIRO/University of Tasmania), Dr Jane McKenzie (marine mammal consultant, Adelaide) and Dr Rebecca McIntosh (Honorary Associate, La Trobe University). These researchers have considerable experience in estimating the age of marine mammals and extensive scientific publications in the field.
The objectives of the Facility are to:
- provide training facilities for researchers new to the field;
- provide a centralised facility housing high-quality equipment for the preparation and analysis of samples for projects that do not have funds or personnel available for training;
- increase the pool of qualified readers for age estimation and validation; and
- provide readily accessible and long-term storage of processed material for future access and reference by the scientific community.
Several students, including four from Università Politecnica Delle Marche, Ancona, Italy, have been trained at the laboratory and many other researchers have made use of the Facility.
In 2007, an intensive workshop was held at the Facility from which a comprehensive manual for marine mammal age determination was developed. The manual is aimed at both new and experienced researchers and includes:
- a history and background of the techniques;
- steps for preparing teeth for thin-sectioning and acid-etching;
- methods for estimating ages from prepared tooth samples; and
- a comprehensive bibliography on marine mammal age determination.
The Marine Mammal Ageing Facility provides the following contract services upon request:
- hire of laboratory space and equipment/consumables for use by experienced researchers for the preparation and estimation of marine mammal ages using teeth;
- training of inexperienced students/researchers in techniques of age estimation of marine mammals using teeth;
- preparation of decalcified, stained, thin-sections of marine mammal teeth for age determination;
- preparation of acid-etched medium to large-sized marine mammal teeth for age determination; and
- provision of age estimates based on either decalcified, stained, thin-sections or acid-etched marine mammal teeth.
For more information contact Dr Catherine Kemper.