Age determination and otolith science

Cefas has an excellent and long-standing reputation throughout Europe for providing high quality otolith processing and age determination services.

We work closely with universities, other fisheries institutes and commercial businesses to provide a full range of services. We were the first institute globally to become ISO 17025 accredited for otolith processing and age determination, and we have a high number of highly skilled age determination specialists.

Age Determination

With over 70 years’ experience of delivering highly accurate and quality controlled age determination on marine finfish, there are in excess of 1.75 million aged fish on our databases gathered since 1977. Our current programme involves more than 20 staff, over 30 species and 60 stocks, equating to over 60,000 fish aged annually.

The other species we age include scallops, whelks, cockles and some freshwater finfish. In collaboration with the British Antarctic Survey we age Patagonian Toothfish, and our researchers are currently investigating the ageing of edible crabs using eyestalks.

Otolith Processing & Micromill Sampling 

Our high quality processing of otoliths and other hard structures are tailored to give the best results on a species and stock basis, using a variety of mounting, sectioning and staining techniques. We routinely handle large volumes of otoliths and our effective sample tracking procedure ensures that this process runs smoothly.

We also have facilities to undertake micromill sampling of otoliths and other hard structures. This is a powerful tool enabling future research. We are able to process and age otoliths and scales from our customers’ own collections to our accredited specifications.


To secure long-term storage of our otolith collection, we have been granted accredited status as a fisheries data archive centre (FishDAC) through the Marine Environmental Data and Information Network (MEDIN). With over a million otolith samples dating back to the 1940s, our archive is a trusted storage facility for our own data and samples, as well as for those from other institutes.


Cefas also offers bespoke training courses in otolith processing and age determination, covering topics and species to meet your specific requirements. Our courses are flexible and modular and can run from a single day to more than a week, depending on your needs.