F. Utter, GENETIC PROBLEMS OF HATCHER-REARED PROGENY RELEASED INTO THE WILD, AND HOW TO DEAL WITH THEM, Bulletin of marine science, 62(2), 1998, pp. 623-640
Long-overdue concerns about the genetic effects of releases of hatcher
y-reared progeny on wild populations have been increasingly addressed
during the past 20 yrs. Because of an extensive history of translocati
on and culture, much attention in both of these categories has focused
on salmonid species. Native salmonids have been indirectly affected b
y translocations through such activities as induced overharvest in sto
ck mixtures, disease introductions, and displacements resulting in fra
gmented populations with reduced numbers and, commonly, localized exti
nctions. Direct genetic effects through introgressive hybridizations o
f translocated salmonids have resulted in replacement of many native p
opulations by hybrid swarms. Genetic effects from salmonid culture hav
e led to losses of variability, both within the cultured populations a
nd between the total cultured and wild populations, and to adaptive di
vergences distinguishing cultured and wild populations. Examples are p
rovided that show that the overall salmonid experience is directly rel
evant to marine culture as well, although special considerations deal
with the lower among-population diversity and greater fecundity often
found in marine species. As marine enhancement programs inevitably exp
and identifying and preserving natural populations are concerns common
to harvest, management, and conservation interests. Coordinated rathe
r than polarized approaches to these concerns best serve all parties a
s well as the irreplaceable resources.