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Table 2. The goals and founder status of four captive breeding programs with reintroduction com- ponents. Species listed in order of increasing number of generations encompassed in the program length. Species California Black-footed Golden lion condor, ferret Guam rail tamarin Heterozygosity goal 90 percent 90 percent 90 percent 90 percent Length of program (years) 200 50 50 200 Number of generations 10 20 22 33 Target population size 150 500 150 550 Number wild-caught 14 18 21 691 Number of contributing founderse 13 10 13 45 Founder genome equivalents, 8 5 5 12 'Heterozygosity goal, program length and target population size have not been officially adopted by program managers; other data from Kieler (1991). 'Founders with currently living descendants. `The number of theoretically ideal founders taking into consideration loss of genetic diversity in the current captive population (Lacy 1989). 'Includes the number of wild-caught tamarins acquired after the captive program was initiated in 1981 in addition to the number of founders and wild-caught individuals alive at the initiation of the program. their descendants) were already in captivity when the tamarin program was initiated in 1981 (Figure 2, A). However, wild animals continue to be available; the 24 wild tamarins that have been added to the captive population since its initiation were animals turned over to the captive breeding program by authorities that had confis- cated tamarins illegally captured from wild populations. In addition, interactive management of the captive and wild tamarin population should expand the founder base for the captive population in the future. Capturing all the individuals at one location may not obtain an adequate sample of the taxon's genetic diversity (Templeton 1990). Genetic surveys of the wild population(s) using electrophoretic or molecular techniques may be helpful in de- termining the geographic distribution of genetic variation in the wild and devising the best sampling plan. Unfortunately, the number of wild animals captured usually does not translate directly into the number of founders. Wild-caught animals may be related, fail to breed or, if they do breed, their descendants may fail to reproduce. For example, although 25 wild ferrets were captured from Meeteetsee, Wyoming, the first 6 died of distemper (Thorne and Belitsky 1989). Several others were known to be parents and offspring, thus reducing the number of potential founders to only 10 presumably unrelated individuals (Ballow and Oakleaf 1989). Furthermore, some potential ferret founders failed to reproduce, while those that did have reproduced unequally, severely skewing their genetic contribution to the population's gene pool. Such processes further erode the genetic contribution of the founders (Lacy 1989). As a result, the current ferret population is founded by the theoretical equivalent (founder genome Managing Genetic Diversity ? 273