The parent’s names, or in fact numbers, represent their studbook number. Upon hatch, every condor is assigned a number which acts as a way to identify each individual. Since 1983, every known condor has been assigned a studbook number in chronological order; the lower the number, the older the condor. A studbook is an important tool in scientifically managing populations of threatened and endangered animals and is updated annually to reflect new hatches, deaths, transfers, and releases. This information may then be used to manage the captive populations to minimize inbreeding and grow populations to a sustainable level. The California Condor International Studbook is maintained and prepared by the San Diego Zoo Safari Park.