Data form a studbook can be utilized in many ways. At a management level, it can be used to locate and place surplus animals and prevent inbreeding. Reproductive information, including generation lengths, reproductive success of individuals, birth season, litter size, fecundity and inter-birth interval can be determined through analysis of studbook data. Inbreeding coefficients, age structure, demography information can also be available in studbooks.
With this information, management questions can be answered, such as: Which animal should reproduce? Is this a population we want to grow? Should further imports be considered?
Besides the actual listing of living and historical populations, studbooks include additional facts such as description, systematics, status of wild populations, current and former distribution, and ecology of wild populations. Studbooks also include a comprehensive bibliography for the species.
A studbook could cover only one subspecies or it could include an entire Taxon. It may be kept on a regional level only, such as North American, or include the entire international captive population. Regional studbooks focus on a specific geographic area, but also include all ancestors regardless of location. Regional studbooks can later expand to an international level if there is a need, especially if animals are frequently transferred from region to region. If there are both international and regional studbooks, keepers will usually share information and may also use the same set of studbook numbers.
A studbook keeper is usually affiliated with a zoological institution or university, and is responsible for collecting all the data and updating the publication on an annual basis. A proposal to start a new studbook must be approved by the American Association of Zoological Parks and Aquariums along with relevant captive management committees.
Most studbooks today are started with the help of the International Species Information System. This database provides a record of all the animals that have been previously reported, but this information needs to be carefully verified and checked for discrepancies. This is accomplished by comparing with the institutional records, published articles, import records, and through personal communications with former owners. The official computer program used for most studbooks is called SPARKS.
Studbooks are distributed to all institutions and persons holding the species and are also made available to other interested parties for the development of management plans. Many specialize libraries also keep limited sets of studbooks.