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Abstract -- Speckled dace (Rhinichthys osculus) are geographically widespread throughout the western United States and occur in many isolated subbasins and interior drainages in south-central Oregon. The ...
Citation Citation
- Title:
- 2009 Foskett Spring Speckled Dace Investigations Progress Report 2009
Abstract -- Speckled dace (Rhinichthys osculus) are geographically widespread throughout the western United States and occur in many isolated subbasins and interior drainages in south-central Oregon. The Foskett Spring speckled dace (R. osculus ssp.) is represented by a single population that inhabits Foskett Spring (Figure 1) on the west side of Coleman Lake (Warner Lakes subbasin) in Lake County, Oregon. Foskett speckled dace was listed as threatened under the federal Endangered Species Act in 1985 (U.S. Fish and Wildlife Service 1985). The Foskett speckled dace became isolated in Foskett Spring at the end of the Pluvial period (~9,000-10,000 years ago). Foskett Spring is a natural spring that rises from a springhead pool, flows through a narrow spring brook into a series of shallow marshes, and then disappears into the soil of the normally dry Coleman Lake (Figure 1). A second population in Dace Spring, located approximately 0.8 kilometer south of Foskett Spring, was established from an introduction of 100 fish from Foskett Spring in 1979-1980 (Williams et al. 1990); however recent surveys have failed to document their continued existence at this location. In 1987, the U.S. Bureau of Land Management (BLM) acquired, through exchange, the 65 hectare parcel of land containing Foskett and Dace Springs. Both sites were fenced to exclude livestock. The Recovery Plan for the threatened and rare native fishes of the Warner Basin and Alkali Subbasin states that Foskett speckled dace will probably not be delisted in the near future because of its extremely isolated range and potential for degradation of its habitat from localized events (USFWS 1997). The primary recovery objective for this species is long-term persistence through preservation of its native ecosystem. The plan further states that the conservation and long term sustainability of this species will be met when: 1) long-term protection of its habitat, including spring source aquifers, springpools and outflow channels, and surrounding lands is assured; 2) long-term habitat management guidelines are developed and implemented to ensure the continued persistence of important habitat features and guidelines include monitoring of current habitat and investigation for and evaluation of new spring habitats; and 3) research into life-history, genetics, population trends, habitat use and preference, and other important parameters is conducted to assist in further developing or refining criteria 1) and 2), above. Actions needed to meet these criteria include protecting the fish population and its habitat, conserving genetic diversity of the fish population, ensuring adequate water supplies are available, monitoring of the dace population and habitat conditions, and evaluating long-term effects of climatic trends on recovery of this fish population. The purpose of this investigation was to determine the status of the federally listed Foskett Spring speckled dace and its habitat. This report updates a monitoring program initiated in 2005 by ODFW (Scheerer and Jacobs 2005) by providing results of monitoring conducted in 2009. Specifically, this monitoring program calls for biannual estimates of population abundance, assessments of distribution and demographic parameters and assessments of physical habitat conditions.
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1632. [Article] Hood River Bull Trout Abundance, Life History, and Habitat Connectivity, 2007 Progress Reports 2007
Abstract -- Hood River bull trout are thought to exist as two independent reproductive units (USFWS 2004), known as local populations (Rieman and McIntyre 1995). The Clear Branch local population is isolated ...Citation Citation
- Title:
- Hood River Bull Trout Abundance, Life History, and Habitat Connectivity, 2007 Progress Reports 2007
Abstract -- Hood River bull trout are thought to exist as two independent reproductive units (USFWS 2004), known as local populations (Rieman and McIntyre 1995). The Clear Branch local population is isolated above Clear Branch Dam, which provides limited downstream fish passage during infrequent and sporadic periods of spill and no upstream passage. Bull trout in this population inhabit Laurance Lake Reservoir and tributaries upstream of Clear Branch Dam. The Hood River local population occurs in the mainstem Hood River and Middle Fork Hood River downstream of the Clear Branch Dam and a small number of adult bull trout migrate each year into the Hood River from the Columbia River (Figure 1). The status of both populations is extremely precarious. The Clear Branch population is at risk of a random extinction event due to low numbers, negative interactions with non-native smallmouth bass, isolation and limited spawning habitat (USFWS, 1998). The Hood River population also appears to be small and is threatened by passage barriers, unscreened irrigation systems, impaired water quality and periodic siltation of spawning substrate by glacial outbursts. Clear Branch bull trout spawn in Clear Branch and Pinnacle Creek. After rearing in these two natal streams for an unknown time period, most are believed to migrate downstream to Laurance Lake Reservoir. Clear Branch bull trout have been documented passing over the dam spillway during high water events (Pribyl et al. 1996) and may provide a recruitment source for the Hood River local population. Adult bull trout tagged at Powerdale Dam have been observed at Coe Branch irrigation diversion and in a trap at the base of Clear Branch dam. These fish may have been attempting to reach spawning areas located upstream of the dam. However, the success of bull trout migrating downstream via the spillway or the possibility of successfully navigating through the diversion network has never been determined. Depending on the water year, the Middle Fork Irrigation District (MFID) may not spill at all, or the timing of the spill may not coincide with the timing of downstream migration, which is currently unknown (East Fork Hood River and Middle Fork Hood River Watershed analysis). Smallmouth bass were discovered in Lake Laurance Reservoir in the 1990s. Creel surveys have shown that large adult bass are caught occasionally in the reservoir and schools of bass fry have been seen by district fish biologist (Rod French, ODFW, personal communication), suggesting that they are spawning successfully. This illegal introduction poses a potential threat to the Clear Branch bull trout population, but its magnitude is unknown because the bass population size and degree of interaction between the two species are unknown. Bull trout and smallmouth bass have significantly different temperature preferences and tolerances, with bull trout being one of the most sensitive coldwater species and bass being a warm water species. Lake Laurance, a relatively high-altitude reservoir at 890 m (2,920 feet), does not provide ideal bass habitat so these two species may have largely non-overlapping distributions or differing activity periods (Terry Shrader, ODFW warmwater fish biologist, personal communication). However, based on past reservoir temperature data (Berger et al. 2005), there are periods in the reservoir when there is potential for bull trout and bass interaction: periods when bull trout are susceptible to bass predation and when juvenile fish might compete for resources. Spawning activity of the Hood River local population has been observed in a few locations within the Middle Fork of Hood River (Figure 1). Although consistent and extensive spawning areas for this population are not known, some of the locations where juvenile rearing or potential bull trout redds have been observed include the Middle Fork Hood River and some of its tributaries: Bear Creek, Compass Creek and Coe Branch (USFWS 2004). However, Coe Branch, Compass Creek, and the Middle Fork are glacial streams with a high volume of sand and silt which may compromise spawning success. No bull trout spawning or rearing has been observed on the East and West Forks of Hood River. The Middle Fork and mainstem Hood River provide foraging, migration and overwintering habitat. Hood River bull trout are also known to migrate into the Columbia River. Two bull trout tagged at Powerdale Dam (RK 7.2 of mainstem Hood River) were recovered near Drano Lake in Washington State; and one was captured 11 kilometers downstream of the confluence of the Hood and Columbia Rivers (USFWS 2004). Every year (usually between May and July), adult bull trout, presumably migrating upstream from the Columbia River, are captured and anchor tagged at Powerdale Dam. Although some of these tagged fish have been observed upstream (one in Coe Branch and three below Clear Branch dam), the spawning destination of fluvial adults within the Hood River basin is largely unknown. Dispersing juvenile bull trout and migrating adults in this local population are threatened by flow diversions with inadequate screening and passage facilities. Several structures are suspected to impede upstream migration or entrain juvenile and adult bull trout into irrigation works (Pribyl et al. 1996, HRWG 1999). These structures include: the diversion at Clear Branch Dam (passage and screening), Coe Branch (passage and screening), and the Farmers Irrigation District diversion (screening) on the mainstem Hood River (HRWG 1999). However, little research has been conducted to assess the impacts of these structures on migrating bull trout. Beyond a general knowledge of the distribution of Hood River bull trout and the nature of anthropogenic factors that potentially restrict their life history and habitat connectivity, little is known about this recovery unit. Baseline information about adult abundance is lacking for both local populations, the potential of a source (Clear Branch) and sink (Hood River) relationship between the two local populations has not been explored, and the migratory life history of adult fish caught at Powerdale Dam is unknown. The degree to which irrigation and hydropower diversions hamper connectivity within the Hood River basin is also poorly understood. Migratory life histories have been viewed as key to species persistence (Rieman and McIntyre 1995; Dunham and Rieman 1999), and understanding movement patterns and associated habitat requirements are critical to maintaining those migratory forms (Muhlfeld and Morotz 2005; Hostettler 2005). Gaining this information is also critical to evaluating bull trout recovery in the Hood River Subbasin (Coccoli 2004). The Oregon Department of Fish and Wildlife (ODFW) initiated a study in 2006 to improve our understanding of the abundance, life history, and potential limiting factors of the bull trout in this recovery unit. This report describes findings for the first two years of the study (2006-2007). Specific study objectives for the first two years were: 1. Determine the migratory life history of Hood River bull trout and assess the potential impacts of flow diversions and two new falls on the Middle Fork Hood River (scoured by the November 2006 glacial outburst) on bull trout migrations. 2. Determine current distribution of bull trout reproduction and early rearing in historical and potential bull trout streams in the Hood River Subbasin. 3. Determine the juvenile and adult life history the Clear Branch local population and develop a statistically reliable and cost-effective protocol for monitoring the abundance of adult Clear Branch bull trout. 4. Assess the potential impact of smallmouth bass on bull trout in Laurance Lake Reservoir.
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Abstract -- Five of the six native Lahontan cutthroat trout (Oncorhynchus clarki henshawi) populations in Oregon exist in the Coyote Lakes basin of southeast Harney County (ODFW 2005). The major drainage's ...
Citation Citation
- Title:
- Population Assessment of Lahontan Cutthroat Trout, 2005 Progress Report 2006
Abstract -- Five of the six native Lahontan cutthroat trout (Oncorhynchus clarki henshawi) populations in Oregon exist in the Coyote Lakes basin of southeast Harney County (ODFW 2005). The major drainage's in the Coyote Lakes Basin are Willow and Whitehorse Creeks. Both drainage's originate on the north slope of Trout Creek Mountain, terminate in the dry Coyote lake bed and are currently isolated from each other or any other basin. Populations of Lahontan cutthroat in Willow and Whitehorse Creeks have been protected under the ESA as a threatened species since 1991 and are also listed as threatened under State of Oregon statute (Hanson et al.1993). Along with changes in management and land use activities, the federal recovery plan for Lahontan cutthroat trout requires the assessment of habitat conditions and population abundance at five year intervals (Coffin and Cowan 1995). Population monitoring of cutthroat in Willow and Whitehorse creeks was initiated in 1985 and has occurred on a five year interval since then (Jones et al. 1998, ODFW Aquatic Inventory Project unpublished data). The goals of this project was to continue population monitoring by obtaining an estimate of Lahontan cutthroat trout in Willow Creek and Whitehorse Creek, and to test the application of the EMAP sampling design (Stevens and Olsen 2004) to obtain this estimate. Additionally, we determined distribution of cutthroat trout in tributaries where presence was suspected but not verified, and monitored distributions of the Antelope Creek populations.
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Abstract -- During 1999, we operated traps to capture upstream and downstream migrant westslope cutthroat trout in the upper mainstem John Day River and three of its tributaries. We also operated a rotary ...
Citation Citation
- Title:
- Native Trout Studies, Annual Progress Report, Project # F-136-R-12
Abstract -- During 1999, we operated traps to capture upstream and downstream migrant westslope cutthroat trout in the upper mainstem John Day River and three of its tributaries. We also operated a rotary screw trap in the John Day River downstream of all tributary traps. These traps were operated from May throughout the contract period. A total of 94 westslope cutthroat trout were captured in all traps, ranging in size from 7 to 39 cm. The screw trap also captured 4,014 fish of six other species. We continued to track cutthroat trout with radio tags implanted in 1998 throughout the life of the tags. These fish displayed a variety of movements, including fluvial migrations from Roberts Creek into the mainstem John Day River, localized movements, and a suggestion of extensive movement. We prepared a draft report of that summarizes information about westslope cutthroat trout in the John Day Basin. We helped determine the distribution and abundance of bull trout and sympatric rainbow trout in four streams of the Middle Fork John Day River.
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1635. [Article] 2006 OPRD- Oregon Chub Population Monitoring on Oregon State Park Lands Progress Reports 2006
Abstract -- Oregon chub Oregonichthys crameri, small minnows endemic to the Willamette River drainage of western Oregon (Markle et al. 1991), were federally listed as endangered under the Endangered Species ...Citation Citation
- Title:
- 2006 OPRD- Oregon Chub Population Monitoring on Oregon State Park Lands Progress Reports 2006
Abstract -- Oregon chub Oregonichthys crameri, small minnows endemic to the Willamette River drainage of western Oregon (Markle et al. 1991), were federally listed as endangered under the Endangered Species Act in 1993 (Markle and Pearsons 1990; Rhew 1993). This species was formerly distributed throughout the Willamette River Valley (Snyder 1908) in off-channel habitats such as beaver ponds, oxbows, backwater sloughs, and flooded marshes. These habitats usually have little or no water flow, have silty and organic substrate, and have an abundance of aquatic vegetation and cover for hiding and spawning. In the last 100 years, off-channel habitats have disappeared because of changes in seasonal flows and habitat characteristics resulting from the construction of flood control dams, revetments, channelization, diking, and the drainage of wetlands for bottomland agriculture. This loss of habitat combined with the introduction of non-native species to the Willamette Valley resulted in a restricted distribution and sharp decline in Oregon chub abundance. The Oregon chub is further threatened by predation and competition by non-native species such as largemouth bass Micropterus salmoides, crappies Pomoxis sp., sunfishes Lepomis sp., bullheads Ameiurus sp., and western mosquitofish Gambusia affinis. To evaluate abundance and distribution of Oregon chub populations, the Oregon Department of Fish and Wildlife has conducted surveys since 1991. Information collected also included the presence of non-native and native species, the characteristics of Oregon chub habitats, the characteristics of potential introduction sites, evaluation of Oregon chub introductions, and life history characteristics (Scheerer 2002, Scheerer and McDonald 2003, Scheerer et al. 2006). The Oregon Chub Recovery Plan (U.S. Fish and Wildlife Service 1998) set recovery criteria for downlisting the species to “threatened” and for delisting the species. The criteria for downlisting the species are: 1) establish and manage 10 populations of at least 500 adult fish, 2) all of these populations must exhibit a stable or increasing trend for five years, and 3) at least three populations meeting criterion 1 and 2 must be located in each of the three recovery areas (Middle Fork Willamette River, Santiam River, and Mid-Willamette River tributaries). In 2006, there were 18 populations totaling 500 or more individuals. Thirteen of these populations met the above criteria. Eight were located in the Middle Fork Willamette drainage, three were located in the Mid-Willamette drainage, and two were located in the Santiam drainage (Scheerer et al. 2006). The status of this species has improved substantially over the past decade and with the addition of a single Santiam population, the downlisting criteria will be met (Scheerer et al. 2006).
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Abstract -- The Warner sucker (Catostomus warnerensis) is endemic to the Warner Valley, an endorheic subbasin of the Great Basin in southeastern Oregon and northwestern Nevada. This species was historically ...
Citation Citation
- Title:
- Warner Valley Fish Investigations- Warner Suckers Progress Reports 2008
Abstract -- The Warner sucker (Catostomus warnerensis) is endemic to the Warner Valley, an endorheic subbasin of the Great Basin in southeastern Oregon and northwestern Nevada. This species was historically abundant and its historical range includes three permanent lakes (Hart, Crump, and Pelican), several ephemeral lakes, a network of sloughs and diversion canals, and three major tributary drainages (Honey, Deep, and Twentymile Creeks). Warner sucker abundance and distribution has declined over the past century and it was federally listed as threatened in 1985 due to habitat fragmentation and threats posed by the proliferation of piscivorous non-native game fishes (U.S. Fish and Wildlife Service 1985). The Warner Valley is a northeast-southwest trending endorheic basin which extends approximately 90 km (Figure 1). The elevation of the valley floor is approximately 1,370 m and the basin is bound by fault block escarpments, the Warner Rim on the west and Hart Mountain and Poker Jim Ridge on the east. The Warner basin was formed during the middle Tertiary and late Quaternary geologic periods as a result of volcanic and tectonic activity (Baldwin 1976). Abundant precipitation during the Pleistocene Epoch resulted in the formation of Pluvial Lake Warner (Hubbs and Miller 1948). At its maximum extent approximately 11,000 years ago, the lake reached approximately 100 m in depth and 1,300 km2 in area (Snyder et al. 1964, Weide 1975). In 2008, precipitation and snow pack were near average and Hart and Crump Lakes never filled completely. In 2007, Crump Lake water levels were very low with less than a quarter of the surface area wetted during the winter. Both lakes have been watered continuously since 1993. The Warner sucker inhabits the lakes and low gradient stream reaches of the Warner Valley. Two life history forms are present that comprise the metapopulation of Warner suckers: lake and stream morphs. The lake suckers are lacustrine adfluvial or potamodromous fish which normally spawn in the streams. However, upstream migration may be blocked by low stream flows during dry water years or by irrigation diversion dams and spawning may occur in nearshore areas of the lakes (White et al. 1990). The stream suckers inhabit and spawn in the three major tributary drainages (Honey, Deep, and Twentymile Creeks). Large lake-dwelling populations of introduced fishes in the lakes likely reduce sucker recruitment by predation on young suckers (U.S. Fish and Wildlife Service 1998). The Recovery Plan for the Threatened and Rare Native Fishes of the Warner Basin and Alkali Subbasin (U.S. Fish and Wildlife Service 1998) sets recovery criteria for delisting the species. These criteria require that (1) a self-sustaining metapopulation is distributed throughout the Twentymile, Honey, and Deep Creek (below the falls) drainages, and in Pelican, Crump, and Hart Lakes, (2) passage is restored within and among the Twentymile, Honey, and Deep Creek (below the falls) drainages so that the individual populations of Warner suckers can function as a metapopulation, and (3) no threats exist that would likely threaten the survival of the species over a significant portion of its range. In 2008, we conducted investigations in Hart and Crump Lakes to quantify the abundance and distribution of Warner suckers, to search for evidence of recent recruitment, and to estimate sucker abundance relative to nonnative fish abundance. In addition we investigated growth and movement patterns. We used Passive Integrated Transponder (PIT) tagged suckers to determine growth rates and movements, tracked radio-tagged suckers to document seasonal spawning migrations, fished a screw trap in Twelvemile Creek to monitor downstream movements, and operated a trap at the Dyke diversion dam on Twentymile Creek to monitor upstream movements.
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Abstract -- The Statewide Trout Management Plan is part of the Oregon Department of Fish and Wildlife's (ODFW) planning program to provide a comprehensive, systematic, long-term approach to the management ...
Citation Citation
- Title:
- Oregon's Trout Plan: A Plan for the Management of Oregon's Trout 1987
Abstract -- The Statewide Trout Management Plan is part of the Oregon Department of Fish and Wildlife's (ODFW) planning program to provide a comprehensive, systematic, long-term approach to the management of Oregon's fish resources. The Plan contains specific goals, objectives, strategies, and guidelines for the statewide management of trout, which are based on state laws, as well as general goals and policies adopted by the Oregon Fish and Wildlife Commission, (hereafter referred to as the Commission). In turn, the Plan provides direction for basin, subbasin, and mini plans developed for individual rivers and water bodies. The relationship of the Statewide Trout Management Plan to other ODFW plans is further discussed in Appendix A. This Statewide Management Plan will direct future trout management and will be reviewed in 6 years. The plan contains brief descriptions of Oregon's trout waters, species, anglers, and economic consequences. The importance of habitat and the use of angling regulations are also discussed. The plan covers all species of native and introduced resident trout and Pacific salmon that are managed in the resident trout program (Atlantic salmon, kokanee, coho salmon, and Chinook salmon) and the anadromous form (searun) of cutthroat trout. Appendix B contains a complete list of fish treated as trout in the plan.
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1638. [Article] Trout in Running Waters 1994 - Draft
Abstract -- This chapter covers management of resident trout species in the Rogue, Applegate, and Illinois rivers and all associated tributary streams (running waters) of the Rogue River basin. Resident ...Citation Citation
- Title:
- Trout in Running Waters 1994 - Draft
Abstract -- This chapter covers management of resident trout species in the Rogue, Applegate, and Illinois rivers and all associated tributary streams (running waters) of the Rogue River basin. Resident rainbow and resident, fluvial, and anadromous cutthroat trout are native to the Rogue River basin. Angling for trout in the Rogue River basin did not become popular until the 1930s. At this time, cutthroat and downstream migrating steelhead were abundant and easily caught from streams in settled areas of the Rogue basin. Mining roads provided easy access to the headwaters of the Applegate and Illinois rivers, Jumpoff Joe creek, and Grave creek where trout fishing was most popular. The California-Oregon Power Company developed roads that provided access to trout fishing waters in the Prospect area in 1912 and the upper Rogue River and its tributaries became accessible in 1927 when the Crater Lake Highway was completed. The Civil Conservation corps developed foot paths and roads into remote parts of the basin in the 1930s. Trout fishing in high pressure areas in the Rogue basin is maintained by stocking. A list of species and numbers of hatchery fish stocked in running waters of the Rogue River basin is presented in Appendix Table A-4.
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1639. [Article] Oregon Chub Investigations, Progress Report 2001
Abstract -- Populations of Oregon chub Oregonichthys crameri, endemic to the Willamette Valley, have been drastically reduced. Factors in the decline of this fish include changes in flow regimes and habitat ...Citation Citation
- Title:
- Oregon Chub Investigations, Progress Report 2001
Abstract -- Populations of Oregon chub Oregonichthys crameri, endemic to the Willamette Valley, have been drastically reduced. Factors in the decline of this fish include changes in flow regimes and habitat characteristics resulting from the construction of flood control dams, revetments, channelization, diking, and the drainage of wetlands. The Oregon chub is further threatened by predation and competition by non-native species such as largemouth bass Micropterus salmoides, small mouth bass M. dolomieui, crappies Pomoxis sp., sunfishes Lepomis sp., bullheads Ameiurus sp., and western mosquitofish Gambusia affinis. We surveyed in the Willamette River drainage in April-October 2000 to quantify existing Oregon chub populations, search for unknown populations, evaluate potential introduction sites, and monitor introduced populations. We sampled a total of 77 sites in 2000. We collected Oregon chub for the first time from Barnard Slough in the Middle Fork Willamette drainage. Oregon chub were last collected from this location in 1983 (Bond 1984). Thirty-one of the 77 sites were new sites that were sampled for the first time in 2000. Forty-six sites, sampled in 1991-1999, were revisited. Three sites were sampled twice. We confirmed the continued existence of Oregon chub at 20 locations. These include naturally occurring populations in the Santiam drainage (Geren Island, Santiam Conservation Easement, Gray Slough, Santiam 1-5 backwaters, Pioneer Park backwater, Santiam Public Works Pond), Mid-Willamette drainage (Finley Gray Creek Swamp) and Middle Fork Willamette drainage (Dexter Reservoir Alcoves, East Fork Minnow Creek Pond, Shady Dell Pond, Buckhead Creek, Oakridge Slough, Elijah Bristow State Park, Rattlesnake Creek, and Hospital Pond) and introduced populations in the Middle Fork Willamette (Wicopee Pond, Fall Creek Spillway Ponds), Santiam (Foster Pullout Pond), and Mid-Willamette drainages (Dunn Wetland, Finley Display Pond). Oregon chub were not found at several locations (Jasper Park Slough, Wallace Slough, East Ferrin Pond, Dexter East Alcove, Hospital lmpoundment Pond, Logan Slough, Green's Bridge Backwater, Camas Swale) where they were collected on at least one occasion between 1991-1999 (Scheerer et. al. 1992; 1993; 1994; 1995; 1996; 1998; 1999; 2000; Scheerer and Jones 1997). Non-native fish were common in off-channel habitats that were surveyed in the Willamette River drainage. Non-native fish were collected from 23 of the 31 new sites sampled in 1999 (74%); no fish were collected at three locations (10%). Western mosquitofish and centrarchids (largemouth bass and bluegill) were the most common non-native fish collected. Oregon chub were introduced into Menear's Bend Pond in the Santiam River drainage in the October 2000. Additional Oregon chub were introduced into Foster Pullout Pond in October 2000, to supplement the 85 fish introduced in 1999. In the summer of 2000, a habitat enhancement project creating new habitat to benefit Oregon chub was completed in the Long Tom drainage (Mid-Willamette River). Seven potential Oregon chub reintroduction sites were monitored and evaluated. These included four sites in the Mid-Willamette River drainage (Finley National Wildlife Refuge Beaver and Cattail Ponds, Ankeny National Wildlife Refuge Dunlin-Woodduck Pond, Long Tom Ranch Pond), one site in the Santiam River drainage (Menear's Bend Pond), one site in the McKenzie River drainage (Russell Pond), and one site in the Coast Fork Willamette drainage (Layng Pond). Estimates of abundance were obtained for naturally occurring populations of Oregon chub in East Fork Minnow Creek Pond, Shady Dell Pond, Elijah Bristow State Park Sloughs, Hospital Pond, Dexter Reservoir Alcoves, Buckhead Creek, Oakridge Slough, Santiam Conservation Easement Sloughs, Geren Island Ponds, and Finley Gray Creek Swamp. Five of these populations showed an increase in abundance in 2000 (East Fork Minnow Creek Pond, Shady Dell Pond, Middle Buckhead Creek, Dexter Reservoir Alcoves, Finley Gray Creek Swamp). Four populations decreased in abundance (or remain depressed) in 2000 (Geren Island, Santiam Conservation Easement, Elijah Bristow Sloughs, Oakridge Slough) (Table 1 ). Abundance estimates for introduced populations of Oregon chub were also obtained. The Oregon chub population in East Ferrin Pond declined from 7,200 fish in 1997 to O fish in 2000, and is presumed extinct. The Oregon chub population in the Fall Creek Spillway Pond totaled 5,030 fish in 2000, compared to 6,300 fish in 1999. The Oregon chub population in Wicopee Pond expanded dramatically from ~50 fish in 1999 to 4,580 fish in 2000. The Oregon chub population in the Dunn Wetland Ponds increased from 4,860 fish in 1999 to 14,090 fish in 2000. The Oregon chub population in Finley Display Pond increased from 360 fish in 1999 to 1,750 fish in 2000. Three of the four largest populations in 2000 were introduced populations. The Middle Fork Willamette River drainage supported the largest number of Oregon chub populations (n=12), followed by the Santiam drainage (n=B), and the Mid-Willamette drainage (n=5). The most abundant Oregon chub populations were found in the Middle Fork Willamette and Mid-Willamette drainages. The Oregon Chub Recovery Plan (U .S. Fish and Wildlife Service 1998) set a recovery goal for downlisting the species to "threatened" and for delisting the species. The criteria for downlisting the species was to establish and manage ten populations of at least 500 adult fish. All populations must exhibit a stable or increasing trend for five years. At least three populations must be located in each of the three sub-basins (Middle Fork Willamette River, Santiam River, Mid-Willamette River tributaries). In 2000, there were 11 populations totaling 500 or more individuals and six of these populations exhibited a stable or increasing trend for the past five years (Table 1 ). Five of these six populations were located in the Middle Fork Willamette drainage. In summary, Oregon chub remain at risk due to their limited distribution compared with their historic geographic range in the Willamette Valley, the loss of suitable habitat and the continued threats posed by the proliferation of non-native fishes, illegal water withdrawals, unauthorized fill and removal operations, and potential chemical spills or careless pesticide applications.
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1640. [Article] Progress Reports 2004: 2004 Oregon Chub Investigations
Abstract -- Oregon chub are endemic to the Willamette River drainage of western Oregon (Markle et al. 1991). This species was formerly distributed throughout the Willamette River Valley (Snyder 1908) in ...Citation Citation
- Title:
- Progress Reports 2004: 2004 Oregon Chub Investigations
Abstract -- Oregon chub are endemic to the Willamette River drainage of western Oregon (Markle et al. 1991). This species was formerly distributed throughout the Willamette River Valley (Snyder 1908) in off-channel habitats such as beaver ponds, oxbows, stable backwater sloughs, and flooded marshes. These habitats usually have little or no water flow, have silty and organic substrate, and have an abundance of aquatic vegetation and cover for hiding and spawning. In the last 100 years, off-channel habitats have disappeared because of changes in seasonal flows resulting from the construction of dams throughout the basin, channelization of the Willamette River and its tributaries, and agricultural practices. This loss of habitat combined with the introduction of non-native species to the Willamette Valley resulted in a sharp decline in Oregon chub abundance. The reduction of habitat and the restricted distribution of the Oregon chub resulted in a determination of "endangered" status under the federal endangered species act (Markle and Pearsons 1990; Rhew 1993). To evaluate Oregon chub population abundance and distribution, the Oregon Department of Fish and Wildlife conducted surveys in April-October 2004. We conducted similar surveys in 1991-2003 (Scheerer et. al. 1992; 1993; 1994; 1995; 1996; 1998; 1999; 2000; 2001; 2002; 2003; 2004; Scheerer and Jones 1997). The survey objectives were to collect information on the status, distribution, and abundance of Oregon chub, the presence of non-native and native species, the characteristics of Oregon chub habitats, the characteristics of potential introduction sites, and to evaluate the success of Oregon chub introductions. In addition, we reviewed and evaluated projects and activities with the potential to impact Oregon chub and their habitats and provided summaries to the U.S. Fish and Wildlife Service.