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<br />....
<br />
<br />Ie same seven bays of
<br />NeV per bay or estuary
<br />averaged 272. The range
<br />J 46.6) per bay or estuary
<br />'om the TPWD MDC in
<br />than both the Ne1 and NeV
<br />Moreover, the estimates
<br />nflated given that the
<br />mrvival probability per
<br />Jably not met. Briefly,
<br />ped yearling or older red
<br />.nced" bays or estuaries
<br />.equivocally identified 30
<br />om Aransas Bay as being
<br />:ribution of brood dams,
<br />inations to the hatchery-
<br />nonrandom, as was the
<br />~ned and wild fish with
<br />within each bay. Karlsson
<br />~se results as indicating
<br />ty among releases, which
<br />ases in total NeR over all
<br />erations suggest that a
<br />occur in Texas bays or
<br />latchery-reared fish.
<br />, that might be employed
<br />PWD-released fish and
<br />a Ryman-Laikre effect:
<br />nating combinations per
<br />Jer of progeny generated
<br />3) increase the number of
<br />ng tanks in each released
<br />e accomplished by using
<br />ach spawning tank, given
<br />ing sires appears greater
<br />ing dams. This approach
<br />~r, as total egg output per
<br />mpromised significantly,
<br />ms than sires appear to
<br />ns. The observed spawn-
<br />also raises the question as
<br />;eason there are dams (or
<br />) progeny to any released
<br />;tudying this issue and, to
<br />~ dams (but not sires) in
<br />ontribute negligibly, if at
<br />Vlonitoring and replacing
<br />, might be a strategy to at
<br />the number of mating
<br />
<br />
<br />practice difficult to impossible to achieve. It also would
<br />likely be unproductive given that the observed
<br />reduction in Ne per spawn due to variation in progeny
<br />produced per mating combination was relatively small
<br />(about 9%).
<br />The third approach, increasing the number of spawns
<br />from different spawning tanks in a released population,
<br />would seem to be the optimal strategy, as the NeR of a
<br />released population would on average be the product of
<br />the average Ne per spawn (estimated here as 2.59) and
<br />the number of spawns from different spawning tanks
<br />included in the mixture. For example, if progeny from
<br />five different spawning tanks were combined into a
<br />single release, the average NeR would be 12.95, a 2.4-
<br />fold increase in NeR. A further 33% increase in NeR (to
<br />17.2) could be achieved by equalizing the number of
<br />progeny from different spawning tanks mixed in a
<br />released population. Even considering a pseudoequal-
<br />ized mixture as simulated above, NeR would still be
<br />increased to 16.1. Given the range (7-27) in the
<br />number of release populations stocked from the MDC
<br />in 2003, the maximum average NeR under this scenario
<br />(i.e., using a pseudoequalized mixture) could range
<br />from more than 110 to about 260, a substantial increase
<br />relative to that estimated under the present-day
<br />program and closer to the average contemporaneous
<br />(NeV) and long-term (Net) effective size estimates of
<br />Saillant and Gold (unpublished) and Turner et al.
<br />(2002), respectively.
<br />
<br />Acknowledgments
<br />
<br />We gratefully acknowledge the help and assistance
<br />provided by personnel, in particular R. Chavez and R.
<br />Gamez of the Texas Parks and Wildlife Department
<br />CCNCPL Marine Development Center in Flour Bluff.
<br />We also thank C. Bradfield and M. Renshaw for help in
<br />the laboratory, D. Gatlin III and W. Neill for help in
<br />obtaining tissues, and T. Turner for helpful comments
<br />on an early draft of the manuscript. Work was
<br />supported by the Texas Sea Grant College Program
<br />(award NAI6RG1078), the Coastal Fisheries Division
<br />of the Texas Parks and Wildlife Department, the
<br />Coastal Conservation Association-Texas, and the
<br />Texas Agricultural Experiment Station (project H-
<br />6703). This paper is number 60 in the series "Genetics
<br />Studies in Marine Fishes" and contribution 160 of the
<br />Center for Biosystematics and Biodiversity at Texas
<br />A&M Universitv.
<br />
<br />NOTE
<br />
<br />]333
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