7842

• UCREFRP Catalog Number: 7842
• Author: Knopf, F. L.
• Title: Biological Diversity in Wildlife Management.
• USFW Year: 1992.
• USFW - Doc Type: 1992.
• Copyright Material: NO

GOLDEN LION TAMARINS
s00
W
N
500
Z
0
i= 400
300
0
a.
200
i=-
CL
Q 100
U
0
........................................... y..'..,..
FROM THE WILD
REINTRODUCED
1970 1975 1980 1985 1990
40
30 w
w
20 2
10 Z
0
YEAR
Figure 2. The historical development of four captive breeding and reintroduction programs: A) golden
lion tamarins; B) Guam rails; C) black-footed ferrets; D) California condors. The dotted line indicates
the target size for each captive population.
1989, Derrickson 1991). Some programs may adopt the "90 percent for 200 years"
goal initially and change to a less demanding one, e.g., "90 percent for 100 years"
if the size and viability of the wild population(s) improve to the point where the
captive population is less critical for preserving the genetic variation of the species.
This approach has been considered by the tamarin management committee.
Setting a specific goal enables estimates, based on population genetics theory, of
the number of wild animals that must be captured and induced to breed in captivity
(the number of "founders" needed for the captive population) and the target pop-
ulation size (the number of individuals that must be maintained in captivity during
the planning period) needed to meet the goal (Soule et al. 1986). Planning to retain
a higher percentage of genetic variation increases the necessary target size. For
example, maintaining 92 percent, instead of 90 percent, of the ferret genetic variation
for 50 years would require a target population of 2,700 rather than 500 individuals.
Managing Genetic Diversity ? 269