The land-based locations make it possible to record and aggregate the data from the port or landing point to the country. These different references are in most cases derived from official sources such as INSEE for French municipalities and regions, Eurostat for European regions and ISO for countries.

Offshore areas are areas used to declare fishing catches or observations for Ifremer's data collection actions. They come from regional fisheries management organisations (RFMOs) such as ICES, NAFO, etc. or from reference systems established by Ifremer in collaboration with local stakeholders, particularly in the outermost regions.

Regulatory areas at sea delimit sectors subject to specific regulations such as EEZs, contiguous areas, Natura 2000 areas, MPAs, etc.

In each of these categories, the reference systems can be organised hierarchically. When it exists, a geographical layer is associated with the reference frame and stored in Harmonie.

Depending on the repositories, they are updated regularly or on request. The associated geographical entity must also be created or modified.