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Microsatellite DNA Analysis and Run Timing of Chinook Salmon in the White River (Puyallup River Basin) PDF Format - [1.24MB]
ACKNOWLEDGMENTS State of Washington General Funds allocated to the Washington Department of Fish and Wildlife for wild salmonid stock recovery genetics and related activities supported this study. All genetic data for this study were collected and statistically analyzed by September 2000; as was information on historical patterns of Buckley trap arrivals and of historical tribal in-river fisheries. All of the above results were incorporated in an initial draft report that was circulated for review at that time. J. B. Shaklee presented an overview of the study results to the South Sound Spring Chinook Technical Committee at its November 1, 2000 meeting. Review (both internal WDFW and external) and revisions of the draft report occurred thereafter until this final report was completed in October 2003.
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Microsatellite
DNA Analysis and Run Timing Summary
We used data from 14
microsatellite DNA loci in five recent collections of chinook salmon in
the Puyallup River system to characterize White River spring-run chinook
salmon. Patterns of allele
frequency variation and direct tests of population differentiation revealed that
the two hatchery populations of White River chinook (at the White River
Hatchery and at the Hupp Springs
Hatchery) were genetically similar to each other but were very different from
the Voights Creek Hatchery fall-run stock. In contrast, a collection of
unmarked and untagged adults sampled at the
Buckley trap on the White River in 1998 and a collection of naturally produced
smolts collected in the lower White River in 2000 were each somewhat intermediate
in their genetic
characteristics (allelic composition and allele frequencies) to the spring-run
and fall-run hatchery populations. Assignment of individual adults and
of individual outmigrating smolts to their most
likely stock-of-origin using the microsatellite DNA data indicated that both
groups consisted of mixtures of fish of spring-run and fall-run origin
(and/or contained fish of inter-stock hybrid
origin). Estimates for each group were approximately 65-70% spring-run ancestry
(and 30-35%
fall-run ancestry).
We reviewed the historical patterns of arrival-timing exhibited by chinook in the White River
using data from Buckley trap interception records from 1949 through 2000. This process
revealed that the predominant pattern of chinook arrivals at the Buckley Diversion Dam (@ RM
24.3) from 1949 through 1970 was that of a spring-timed chinook run (majority of arrivals prior
to July 1st) with a small percentage of fall-timed individuals (arrivals after September 30th). In
contrast, substantial runs of later-timed chinook (average of 88% of the run arrived at Buckley
after the second week in August) dominated the arrivals in the nine years from 1987 through
1995. Because the Buckley trap arrival patterns from 1971 through 1986 were much more
variable and the run sizes from 1977 through 1986 were much smaller due to the intensive
recovery program operations in these years, it was difficult to generalize about the nature of the
chinook runs during this time period. Recent arrival patterns (1996 to present) showed a slightly
increasing percentage of spring-timed fish and a concomitantly decreasing proportion of falltimed
fish at the Buckley trap. The increased numbers (and proportion) of spring-timed chinook
and decreased proportion of summer/fall-timed chinook seen in the upper White River in the past
five years may be attributable to successful spring-run chinook production by the multi-agency,
hatchery-based White River Spring Chinook Recovery Program.
We also examined the patterns of estimated historical gillnet fishery harvests in the lower White
and Puyallup Rivers in five selected years for information regarding patterns of run-timing. The
temporal patterns of estimated catches in the years examined suggested that both spring-timed
and fall-timed chinook runs were present in the lower White and/or Puyallup Rivers in 1954,
1955, 1957, 1966, and 1977. The timing of Buckley trap arrivals and the temporal patterns of
these estimated fishery harvests suggested to us that the fall-timed chinook were confined to the
lower White River (below the Buckley trap) from 1954 through 1977 (except in 1973). Whether
or not a native fall-timed chinook run occurred in the upper White River prior to 1954 is unclear,
but Buckley trap counts for 1949 - 1953 suggest this possibility.
Although the basis for the appearance of the fall-timed run in the years since 1977 is unknown,
increased minimum in-stream flows since 1987 and/or changes in hatchery operations may well
have contributed to this change.
Given that there is little evidence that the fall-timed chinook run observed in the upper White
River in the last 20 or so years is native to this system, we are concerned about the potential for
interbreeding and/or competition between the presumed native White River spring-run stock and
these fall-timed fish.
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