7890

• UCREFRP Catalog Number: 7890
• Author: U.S. Fish and Wildlife Service.
• Title: Region 6, Fish and Wildlife Service Guidelines Directing Captive Propagation Of Listed And Candidate Fish.
• USFW Year: 1996.
• USFW - Doc Type: \
• Copyright Material: NO

diversity both within and among wild stocks. Risk assessment must be
addressed in each specific reintroduction plan (See Box 4).
Box 4. Genetic risks, hatchery activities causing such risks, and genetic
processes related to these risks (expressed as changes from natural
patterns). Modified from Kapuscinski et al. (1993).
Genetic risk Hatchery activity causing risk Genetic process
Extinction Excessive numbers of adults removed from Increases in
wild stock or population for development genetic drift
of broodstocks. ..and inbreeding
Loss of genetic Low number of parents mated. Increases in
diversity with- genetic drift
in stocks or Inappropriate breeding design. and inbreeding
populations
Inappropriate fertilization method.
Captive breeding changes the natural
genetic variation in families.
Founders for broodstocks differ from wild
or supplemented stocks or populations in
genetic diversity, life history patterns,
or adaptability to the environment of the
wild stock or population.
Loss of genetic
diversity among Broodstock collected from stocks or
populations th
t Immigration:

stocks or popu-
tions a
are genetically
unrelated to wild or supplemented Chan es in
g
genetic
interbreeding stocks or populations.
atterns;
p
Outbreeding
depression.
Inadvertent
artificial Broodstock not collected throughout
th Artificial

selection e spawning season. selection:
Mated adults are from a nonrandom patterns of
atterns
p
sample of their cohort with respect
t natural
o genetic performance traits because
f selection;
o
nonrandom mortality during incuba-
tion, rearing
or holding Changes in
,
. amounts of
Genetic swamping of wild stocks through
natural
s
election
stocking of large numbers of closely
related individuals or unequal family lots.
1 7_?
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