I wouldn’t normally encourage you to Google “studbooks”, especially for those readers that visit us while they should be working. (Crickets)

What is a studbook? I’ll let the FAQ at Studbooks.org, answer that one:

A studbook is literally a register in which the origin (descent) and characteristics of the registered animals of one race or species are drawn up. In case of the ESF, this concerns a group of reptile and amphibian species. A studbook can arrange a number of things: management of an animal species in captivity, countering inbreeding by working with breeding programmes and knowledge collection and publication.
This means that the studbook keeper keeps track of which animals are being cared for at which location and which animals reproduce, the goal of this being to guarantee the genetic health of the population on the long term. Animals and their offspring can be exchanged between (aspiring) studbook members, with the studbook keeper possibly playing a mediating / advising role. The studbook keeper can be consulted if there are questions regarding the husbandry and breeding of the species.
Once a year, the studbook keeper publishes an annual report, in which mutations and successes of the past year are noted.

The FAQ also explains why studbooks are important:

Especially for species that are in danger of extinction (in captivity and/or in the wild), it is vitally important to keep the gene pool of the population as broad as possible. The smaller the population, the bigger the chance of risks that come with inbreeding. With every individual animal that dies in a small population (such as the European captive population), part of the genetic variation disappears that is necessary for a genetically healthy population. The same applies for an animal that does not reproduce: this individual is genetically `dead` for its populations future existence, unless an effort is made to breed with the individual.
The collection and transfer of knowledge means that an effort is made to collect, and eventually publish, as much information as possible about the husbandry and breeding of a studbook species. This way, one person can be consulted instead of `the wheel having to be reinvented` again and again.

In essence, through collaboration, these zoology “dating sites” can best match breeding pairs based on data captured in various sources and tabulated in a common space. Steve Feldman, spokesperson for the Association of Zoos and Aquariums which oversees the majority of studbooks for exotic species in the United States was quoted in the Sunday New York Times ”to paraphrase an old Jeff Foxworthy joke, it’s important that your family tree forks. This way we can have a genetically diverse population.”