Endangered and Threatened Fishes in the Klamath River Basin Causes of Decline and Strategies for Recovery (2004) / Chapter Skim
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7. Fishes of the Lower Klamath Basin
7. Fishes of the Lower Klamath Basin
Pages 250-286
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From page 250... ...
Given that the native anacTromous fishes support important tribal, sport, ancT commercial fisheries ancT have high iconic value, there is wiclespreacT support among stakehoiclers, both insicle ancT outside the basin, for restoration of these fishes to their earlier abundances. Restoration efforts wouicT most rationally apply to all native fishes, not just those listecT or proposed for listing uncler the fecleral EnciangerecT Species Act (ESA)
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From page 251... ...
tslvawytsclva Southern Oregon-Northern A California ESU Upper I(lamath and Trinity rivers ESU Fall run TTS, probably multiple runs Poorly known Poorly known TTS, important fishery May not spawn in river Most widespread fish in basin State special concern A/N Common A Federally threatened Commonest salmon below mouth of Trinity River A Commonest salmon in both rivers Found also in Smith and Rogue rivers TTS, huge runs now gone, lowermost river only Small population .
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From page 252... ...
In aciclition, nonnative fishes come clown continually from the upper I(lamath basin. COHO SALMON The coho salmon (Figure 7-1)
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From page 253... ...
gibbosus N Uncommon Abundant in upper basin Largemouth bass, N Common Ponds and reservoirs Micropterus salmoides Spotted bass, N Locally common Only in Trinity River M punctulatus reservoirs Smallmouth bass, N Locally common Only in Trinity River M
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From page 254... ...
Life History Coho salmon in the I(lamath basin have a 3-yr life cycle (3 yr is the time from spawning of a parent to spawning of its progeny) , about the first 1418 ma of which is spent in freshwater, after which the fish live in the ocean until they return to freshwater to spawn at the age of 3 yr.
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From page 255... ...
The presence, however, of small numbers of aclult coho in the fish kill of September 2002, indicates that some coho begin migration without these stimuli. Most spawning takes place in tributaries, especially those with forested watersheds, but some main-stem spawning has been recorclecI (Trihey ancI Associates 19961.
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From page 256... ...
NMFS (2002) has iclentifiecI, in aciclition to the Shasta, Scott, Salmon, anti Trinity rivers, six creeks between Iron Gate Dam anti SeiacI Valley, 13 creeks between SeiacI Valley ancI Orieans, anti 27 creeks between Orieans anti the mouth of the I(lamath as important coho habitat in the I(lamath basin.
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From page 257... ...
TABLE 7-3 Pools Containing luvenile Coho Salmon, Chinook Salmon, anti SteelheacI Along Main Stem of I(lamath River, 2001' as Determined in Snorkeling Surveysa No. of Mouth No.
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From page 258... ...
Although 2001 was a year of exceptionally low flows, Table 7-3 suggests that coho juveniles are uncommon in the main stem in early summer ancI become progressively less common as the season progresses. luvenile coho are virtually absent from the main stem, inclucling pools at tributary mouths, by late summer, even though juvenile Chinook ancI steelheacI persist in these habitats.
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From page 259... ...
Thus, the evidence points to the conclusion that juvenile coho are not occupying either the estuary or the main stem through the summer. One proposal for increasing the survival of juvenile coho in the main stem in summer has been to release more water from Iron Gate Reservoir to increase the habitat for juvenile coho, as clefinecI by analogy with habitat used by juvenile Chinook salmon, ancI to recluce ciaily temperature fluctuations in the river, thus removing the potentially lethal temperature peaks (Chapter 41.
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From page 260... ...
Ocean survival clepencis on a number of interacting factors, inclucling the abundance of prey, density of preciators, the clegree of intraspecific competition (inclucling that from hatchery fish) , ancI fisheries (NRC 19961.
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From page 261... ...
Persistently poor conditions in freshwater, such as exist throughout the Klamath basin today, make the recovery of populations clifficult, however, even when ocean conditions are favorable anti fisheries have been shut clown or reclucecI. When ocean conditions are poor, the positive effects of restoring of salmonicI habitat in streams may be masked (Lawson 1993, NRC 19961.
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From page 262... ...
In recent years, the Trinity River Hatchery has releasecI an average of 525~000 coho per year anti the Iron Gate Hatchery about 71~000 per year (CDFG 20021' although historically the Iron Gate Hatchery has releasecI about 500,000 coho per year (CDFG, unpublishecI ciata, 20021. The coho typically are rearecI to the smolt stage anti marked with a maxillary clip before release, which occurs between March 15 anti May 1.
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From page 263... ...
Annual runs have ranged from about 30~000 to 240~000 fish in the last 25 yr (CDFG, unpublishecI ciata, 20021' although runs were much larger historically (Snycler 19311. Chinook salmon spawn ancI grow primarily in the main stem of the Klamath River, in the larger tributaries (such as the Salmon, Scott, Shasta, ancI Trinity rivers)
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From page 264... ...
ESU ancI the Upper I(lamath ancI Trinity rivers ESU (Myers et al.
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From page 265... ...
In 1993-1996, spawning in the reach between SeiacI Creek ancI within 40 mi of Iron Gate Dam on the main stem began in the second week of October, peaked in the last week of October, ancI was completecI by the micicIle of November (USGS 19981. This spawning period coincides with cleclining temperatures, which by early November are within the optimal range for incubation of cleveloping embryos (4-12°C)
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From page 266... ...
Peak numbers occur in March or early April for the Shasta River ancI from the micicIle of April to the micicIle of May in the Scott River. A survey of main-stem pools at the mouths of creeks in 2001 indicates that juveniles can be founcI in the main stem from lanuary through September, but abundances are consiclerably reclucecI by August ancI September (T.
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From page 267... ...
Hatcheries Hatcheries for Chinook salmon have been operating continuously since 1917. Both the Iron Gate Hatchery ancI the Trinity River Hatchery produce large numbers of spring-run ~ 13 % ~ ancI fall-run ~ 87% ~ juvenile Chinook of native stock (Myers et al.
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From page 268... ...
Wales (1951) noted that the clecline hacI multiple causes, most relatecI to fisheries ancI lancI use in the basin, but laicI much of the blame on I(lamath River lampreys: the lampreys preyecI extensively on the salmon in the main stem when low flows clelayecI their entry into the Shasta River.
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From page 269... ...
~ , ~ (West 19911. Because most of the streams in which they reside also are likely to be used by juvenile coho salmon, interactions between the two species are likely (see O'Neal 2002 for information specific to the I(lamath)
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From page 270... ...
The Trinity River Hatchery releases over 1 million juvenile spring-run Chinook every year, usually in the first week of rune. Apparently, all spawners in the main-stem Trinity River below Lewiston Dam are of hatchery origin.
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From page 271... ...
They can tolerate minimal depths ancI flows ancI so can be founcI in the smallest accessible tributaries ancI in the main river channels. Although spawning occurs mainly in tributaries, the juveniles distribute themselves wiclely, ancI many move into the main stem.
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From page 272... ...
Hatcheries The Iron Gate Hatchery produces about 200,000 ancI the Trinity River Hatchery about 800~000 winter steelheacI smolts per year (Busby et al.
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From page 273... ...
luveniles probably occupy mainly the same upper stream reaches in which they were spawned, that is, above the areas in which most winter steelheacI spawn ancI rear but where coho are likely to be present. Other aspects of their life history are similar to those of winter steelheacI, inclucling a predominance of 2-yr-oicI smolts ancI the presence of half-pounclers (Hopelain 19981.
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From page 274... ...
1995, Moyle 20021. Chum Salmon Periodic observations of aclult chum salmon ancI the regular collection of small numbers of young suggest that this species continues to maintain a small population in both the I(lamath ancI Trinity rivers (Moyle 20021.
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From page 275... ...
19951. Their life history in the I(lamath River is poorly clocumentecI but is apparently similar to that of winter steelheacI.
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From page 276... ...
Spawning takes place in the lower main stems of the I(lamath ancI Trinity rivers in creep pools with strong bottom currents. luveniles occupy the river until they are 1-3 yr oicI, when they move into the estuary ancI then to the ocean.
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From page 277... ...
The relationship between the native nonanaciromous ancI anaciromous species has not been worked out in the I(lamath, but the ciace, stickleback, scuipins, ancI suckers are probably subsiclizecI by nutrients brought into the streams by the anaciromous fish ancI may suffer heavy predation, especially in the larval stages, by juvenile salmon ancI steelheacI. Nonnative Species The lower I(lamath basin is still clominatecI by native fishes, but other species have a strong presence in highly alterecI habitats, such as reservoirs ancI poncis.
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From page 278... ...
The sponsors of the NRC stucly on enciangerecI ancI threatened fishes asked the NRC committee to stucly information on the fish kill of 2002 ancI inclucle the analysis in its final report. While it is reasonable that this issue be covered in the committee's report, it is also important to note that the fish kill primarily affected Chinook salmon, for reasons that are explainecI below, ancI not the threatened coho salmon that is the focus of attention for the NRC committee in its work on the lower Klamath basin.
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From page 279... ...
. Indirect Causes of Mortality Low flow in the I(lamath River main stem is the most obvious possible cause of stress leacling to the lethal infections of fish in the lower I(lamath River cluring 2002.
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From page 280... ...
that accumulates below the 3,000 2,500 2,000 us ~ 1,500 ·_. 1,000 500 o I Cal Klamath | ~ Iron Gate —2026 77 1489 ~ 11894 ~1857 1988 1991 1992 1994 2001 2002 FIGURE 7-3 Mean flows of the I(lamath main stem at I(lamath (near the site of the 2002 fish kill)
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From page 281... ...
Information on water temperature is sketchier, but also indicates that average maximum water temperatures fell within the range of water temperatures in previous years of low water when there were no fish kills. The USGS macle comparisons of the I(lamath River with the Rogue River, which is locatecI nearby ancI has more comprehensive temperature records.
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From page 282... ...
These changes clicI not result in fish kills cluring the low-water year of 2001, but flows in 2001 were not as low as those in 2002. Thus, a current hypothesis of CDFG is that a change in channel geometry has created new conditions that are cletrimental to fish at low flows even though such flows previously clicI not leacI to high mortality.
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From page 283... ...
. The emergency release of 500 cfs of aciclitional water from Iron Gate Dam by USER, which arrived long after the fish kill hacI enclecI, lackecI any specific justification.
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From page 284... ...
This is particularly true for the lowermost reach of the main stem, below the Trinity River, which may be either cooler or warmer in late summer than the main stem, clepencling on the amount of water being releasecI from Lewiston Dam. Millions of juvenile fish, inclucling Chinook salmon, steelheacI, ancI coho are releasecI into the I(lamath anti Trinity rivers each year by the Iron Gate ancI Trinity River hatcheries, which were built to mitigate salmonicI losses created by large clams.
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From page 285... ...
3. The biology of nonanaciromous native fishes ancI macroinvertebrates in the basin is largely unknown, inclucling basic descriptions of life histories ancI environmental requirements ancI their relationships to coho salmon ancI other anaciromous fishes.
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From page 286... ...
The effect on the lower river of changing flows from the Trinity River neecis to be evaluatecI, as clo the potential benefits of comanaging flow releases from the clams on the Trinity anti Upper I(lamath rivers.
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