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- Oklahoma Department of Wildlife
Conservation
Contact: Gene Gilliland (405) 325-7288;
ggillokla@aol.com
- Comparison of striped bass egg production and
juvenile striped bass abundance between the Washita and Red rivers (3rd
year of who knows how long a project)
Proposed desalinization projects in the upper Red River drainage
threaten to compromise striped bass recruitment in Lake Texoma. Altered
flow regimes and increased turbidity are the likely outcomes of these
proposed projects. Striped bass reproduce in both the Washita and Red
rivers, yet the proportion of recruitment from each system is unknown.
The Oklahoma Department of Wildlife Conservation, the University of
Oklahoma, and Oklahoma State University are cooperating on an intensive
study to determine recruitment mechanisms of striped bass in both river
systems. Drift net samples of striped bass eggs have been collected over
the past three years. Principle spawning location on the Washita River
was known previously and verified with this study. Additional spawning
locations on the Washita River were identified and spawning locations on
the Red River have been located under this study. CPUE (number of
eggs/m3) is significantly higher in the Washita River than in the Red
River, yet numbers of juvenile striped bass collected in seine samples
has been higher in the Red River arm of Lake Texoma. Based on
differences in channel morphology between the Washita and Red rivers, we
concluded that sampling efficiency of the drift nets were different
among sites on the same river and between rivers. We are currently
evaluating the use of surrogate striped bass eggs (gellan balls) to
estimate sampling efficiency at each station on each river. As
suspected, preliminary estimates indicate that sampling efficiency is
higher on the Washita River than on the Red which would account for the
discrepancy between the egg-net samples and the seine samples.
Availability of plankton at the time and place of
first feeding (larval) are being investigated as a cause of differential
mortality between rivers. Mesocosm experiments have been set up to
evaluate this in a controlled environment. Daily growth rings are being
used to match peaks in spawning activity (egg catches in drift nets) to
sizes of juvenile striped bass collected in June seine samples. Diets of
juvenile striped bass are also being examined. Differences in forage
availability (age-0 shad) and overwinter survival of age-0 striped bass
between arms of the lake are being monitored using gill nets.
Jeff Boxrucker (405) 325-7288;
jboxrucker@aol.com
- Determining the degree of hybridization in the
smallmouth bass population of Broken Bow Reservoir and the Mountain Fork
River
A recent allozyme survey across the natural range of smallmouth bass
demonstrated that the native populations on the western edge of the
Interior Highlands (Ozark Plateau and Ouachita Mountains) represent the
two most divergent lineages of the species; these are referred to as the
Neosho and Ouachita smallmouth bass. Prior to publication of this
information, the Oklahoma Department of Wildlife Conservation (ODWC)
introduced fingerling “Tennessee lake strain” smallmouth bass to
Tenkiller Reservoir (1991 and 1992) and Broken Bow Reservoir (1993).
Prior to these stockings, Tenkiller and Broken Bow reservoirs supported
native populations of Neosho and Ouachita smallmouth bass, respectively,
although in low numbers. Concerns over loss of genetic diversity of
these native populations and in response to the findings of the allozyme
survey, ODWC discontinued stockings in waters supporting native
smallmouth bass. However, improvements in smallmouth bass population
structure in these two reservoirs coincided with stocking the “lake
strain” fish which has let to angler demands to expand the “lake strain”
stockings into drainages supporting the native strains.
Variation in smallmouth bass microsatellite DNA loci
was used to determine the degree of hybridization in Tenkiller and
Broken Bow reservoirs and in the impounded streams above the reservoirs.
The results indicated that 85-90% of the genome in samples from
Tenkiller Reservoir and 41% of the genome in samples from Broken Bow
Reservoir were non-native. It is likely that given a few additional
generations of random mating, all individuals will carry
mixed/non-native genotypes. The quality of the smallmouth bass fishery
may be dependent on the growth and survival of the “lake-strain” or F1
hybrid. If so, the quality of the fishery may decline as genetic
recombination increases the abundance of Fx individuals. No
introgression of the “lake-strain” genome into the tributary streams
containing the native strains was found. However, with time,
introgression is likely to occur. No samples were collected from the
lower reaches of the streams nor from the “up-lake” portions of the
reservoirs, areas in which introgression into the stream populations
would be most likely to occur.
These previous studies are currently being followed up
by collecting additional samples from Broken Bow Lake and up stream in
the Mountain Fork River. Up-lake transition (between lake and stream)
were intensively sampled with only 1 smallmouth bass collected in 6.5h
of electrofishing. Samples were also collected from 3 zones of the Upper
Mountain Fork River progressively upstream from Broken Bow Lake. Genetic
analysis is currently being conducted.
Growth and mortality rates of smallmouth bass from
Broken Bow Lake and the three zones in the Upper Mountain Fork River
were compared. Not surprisingly, growth rates of smallmouth bass from
the reservoir were higher than from the river, mean length of age 2
collected in the fall were 289 mm and 224 mm, respectively. Mortality
rate of the smallmouth population in the lake was 71% and in the river
was 40%. Genetic analysis is currently being conducted on individual
fish to determine if growth and mortality differences between systems
can be linked to introgression rates.
Caution: Even though only one individual was found in
the transition zone, which might indicate natural barriers of movement
between lake and stream, the potential exists for anglers to move fish
from the lake to pools upstream in the Mountain Fork River. Genetic
mixing is likely to occur over time. Whether or not this is a “good” or
“bad” thing may end up being an ethical decision.
Jeff Boxrucker (405) 325-7288;
jboxrucker@aol.com
- Kaw Lake White Perch
Spring, summer, and fall sampling since 2001 has revealed little
change in the white perch population of Kaw Reservoir. Catch rates of
white perch have remained low with all sampling gears. Gill net and trap
net sampling has produced the least variable catch rates. Electrofishing
has proven quite ineffective for the collection of white perch. This
population has not (yet?) exploded as has happened in other Midwest and
Plains states following introduction. The slow growth of Kaw white perch
is similar to other regional water bodies. The white bass and white
crappie populations have not shown any negative effects since the white
perch introduction. Stomach sampling of these two species is ongoing for
study of potential diet overlap and competition with the white perch.
Kurt Kuklinski, (405) 325-7288;
KurtKuk@prodigy.net
- GIS Project
A study relating physical, geographical features to license sales and
other human resources data is ongoing. The objective is to determine and
better understand relationships between geographical features (water
bodies, access to angling opportunities, license dealers, etc.) and
license sale trends. Results are expected to assist in recruitment and
retention potential, as well as assisting in the most beneficial
marketing strategies. Analysis is ongoing.
Kurt Kuklinski, (405) 325-7288;
KurtKuk@prodigy.net
- Electrofishing Sampling Changes
A committee of ODWC personnel recently reviewed and changed some of our
basic standardized sampling protocol. The resulting procedures provide
for more robust statistical analysis. One major change in our sampling
procedures was creating guidelines for collecting and analyzing a set of
independent samples rather than analysis of a lake as a single sample.
Specifically, a predetermined number of 15-minute samples (based on lake
size) is collected, and a mean catch rate calculated based on these
samples. Previous analysis was largely based on total fish collected and
total effort expended. Specific target length groups were also modified
based on regulations by species. The changes have been readily accepted
because the resulting lake analyses are easier to read and provide
cleaner presentation of the data.
Kurt Kuklinski, (405) 325-7288;
KurtKuk@prodigy.net
- Aquatic Plant Introductions
Six years after initial introductions, aquatic plants are surviving in
exclosures at Arcadia Reservoir. However, little or no spread has
occurred outside the fenced areas except for water willow and to a
lesser degree, pickerel weed and bullrush. In 2003, several hundred
“tomato cages” and hundreds of feet of fencing were removed (these
exclosures contained no plants). The scrap was bundled and sunk in
marked “brush piles.”
At Lake Thunderbird, two-year old plots are showing
excellent growth and some minor spread of American pondweed, water
stargrass, najas, and sago pondweed. One significant development was the
success of Canadian elodea. It was growing and filling fenced areas
following planting of fragments last summer. Pickerel weed was seeding
and seedlings were found along the shoreline outside the cages.
We have been using 1" hex mesh vinyl-coated chicken
wire the last two years and it still looks like new. Easy to work
(flexible) with and cheaper than welded wire, it appears to be more
durable too. Welded wire, although galvanized, was rusting out in a
year’s time.
Gene Gilliland, 405-325-7288;
ggillokla@aol.com
- Water Level Management Plans
Agency Administrators are planning a full review of all water level
management plans we have with the Corps of Engineers. Current plans are
not always followed and many have waterfowl components that compromise
fishery benefits. Negotiations continue (slowly) with the Grand River
Dam Authority about water levels, shoreline development permitting and a
resource management plan for Grand Lake.
Barry Bolton, 405-521-4646;
bbolton@odwc.state.ok.us
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