As a first result the migratory status has been assessed, using major reviews and handbooks. Note the high number of fish species with unknown migratory status. More detailled literature searches are planned to improve our knowledge about this category. It is an intergovernmental treaty of global scale. Maps and GIS Geographic information about species distributions exists in a huge variety of forms, not necessarily visualized as maps.
Most data are point data, which are often summarized as a distribution area.
Vector formats consume less computer storage resources and can easily be transformed to different projections or exported to other GIS-projects, to cover further aspects relevant for conservation. Maps are interactive, and information from the database can be retrieved by clicking to certain map sites. The core of the database is the population table , because - populations within one species exhibit different migratory behaviour. It summarizes basic information such as population size, threats, regional conventions, etc. Hot spots are aggregation areas such as staging posts or breeding grounds for birds, bat wintering caves or any other area where a major percentage of a population aggregates in high concentration.