Status and Conservation of Oregon s Interior Redband Trout. Oregon Department of Fish and Wildlife Native Fish Investigations Project

Transcription

1 Status and Conservation of Oregon s Interior Redband Trout Oregon Department of Fish and Wildlife Native Fish Investigations Project

2 Oregon s s Inland Redband Trout Legend Lakes Streams Klamath Great Basin Snake

3 Great Basin Redband Trout Oncorhynchus mykiss newberrii Rainbow trout and cutthroat trout diverge: late Pliocene (~2,000,000 ya) Rainbow trout invade the Great Basin: Pleistocene (~70,000 ya) Warming and drying of the Great Basin isolates rainbow trout Great Basin redband trout occur in 6 isolated basins with no connectivity Redband Trout are isolated above dams and diversions in Klamath and Snake

4 Redband Trout SMUs and Populations Great Basin Redband Trout SMU's and Populations Silvies Silver Poison Prater Cow Coffeepot Rattlesnake Buck Fort Rock Malheur Lakes Bridge Riddle Jenny Wood Cascade Complex Lower Williamson Klamath River Upper Williamson Lower Sprague Upper Klamath Basin Lost River SIlver Upper Sycan Foster Chewaucan Chewaucan Warner Lakes Rock Willow Upper Sprague Honey Crooked Guano Thomas-Bauers Complex Cottonwood Upper Deep Upper Muddy Drews Deadman Antelope Lower Deep Lower Crane Drews Cogswell Dry Tandy Kelley Twentymile Fall Goose Lake McCoy Blitzen Threemile Home Skull Catlow Valley

5 Species Management Units and Populations Species Management Units are defined as the major pluvial lake basins of the Great Basin. Are geographically isolated from populations in other SMUs and may be genetically distinct. Coincide with ODFW management plans and the USFWS Status Review of Great Basin redband Trout. Populations were based on geography, movement patterns and genetic data.

6 Oregon Great Basin Area: 40,000 km 2 16% of Oregon s area distribution of redband trout in wadable streams Pop: 14,000 people 0.4% of Oregon s pop 6 interior basins with redband trout Northern Basin & Range Elevation: 1,246-2,964 m (4,088-9,725 ft) Annual ppt: cm (6-51 in)

7 Great Basin Redband Trout Redband trout persist in areas of higher elevation/precipitation Diverse habitats gave rise to diverse life histories Majority of redband trout inhabit headwater streams - stream resident form Pluvial lakes present in Goose, Warner, and Malheur Lakes basins - adfluvial form adfluvial form stream resident form

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9 Previous Redband Trout Assessments 1997: Redband trout petitioned to be listed under ESA 1999: ODFW surveys Great Basin redband trout - 950,000 fish (± 21%) 2000: USFWS denies listing of redband trout 2005: Status Review of Oregon s Native Fishes

10 ODFW Status Review

11 Evaluation Criteria 1. Existing Populations 2. Habitat Use Distribution 3. Abundance 4. Productivity 5. Reproductive Independence 6. Hybridization

12 Trout Status Criteria Existing Populations Extinct or functionally extinct Population delineation based on Bowers et al, input from regional staff Distribution Pass if meet two of three criteria: 1) > 10% of total stream distance 2) Greater than 5 miles 3) Connected to other populations

13 Redband Status Criteria Abundance Data from Dambacher 2001, and district staff Guidelines based on Dambacher and Jones 2007 Low <0.059 fish m-2 Moderate fish m-2 High >0.2 fish m-2 Pass if moderate or high in 3 of the past 5 yrs. Productivity Not quantitatively assessed due to a lack of or inconsistent data Consider distribution and abundance high densities with adequate distribution = pass isolated populations (no migratory life history) = fail presence of non-native salmonids =?

14 Reproductive Independence Current and historic stocking records Failed if currently stocked, or if genetic analysis indicates significant interaction Hybridization Redband Status Criteria Pass if hybrids are rare or non-existent If data are not specific, then fail if con-generic non-native fish are sympatric

15 Conservation Status Score for SMU Each of these attributes was evaluated for every population based on benchmark values related to species viability, persistence probability, and conservation risks. Criteria for individual SMUs were met when at least 80% of existing constituent populations met the standard. Risk categories were assigned based on the number of interim criteria met by each SMU.

16 Implementation of Criteria Scoring of Interim Criteria place SMUs in one of three conservation risk categories: At Risk SMU does not meet at least four of the six criteria. Potentially at Risk SMU meets four or five criteria. Not at Risk SMU meets all criteria.

17 Status of Redband Trout Not at risk Potentially at risk At risk Extinct Fort Rock Malheur Chewaucan Klamath Goose Warner Catlow

18 Scoring of Status Criteria for Redband Trout SMUs Upper Klamath 10 80% 40% 0% Goose Lake 13 Chewaucan 4 Fort Rock 3 Warner Lakes 4 Catlow Valley 5 Percent of Populations Meeting Criterion 80% 40% 0% 80% 40% 0% 80% 40% 0% 80% 40% 0% 80% 40% 0% Malheur Lakes 10 80% 40% 0% Existing Populations Distribution Abundance Productivity Reproductive Independence Hybridization

19 Factors Limiting Redband Productivity Flow diversion Degraded Stream & Riparian Habitat Migration Barriers Competition with exotic salmonids Climate regime

20 ODFW Redband Trout Study 2007: ODFW s Native Fish Investigations Project initiates a six-year study to assess status and trends of Great Basin redband trout Key Objective: - To assess the response of fish populations to changes in climatic conditions and evaluate subsequent shifts in population abundance and structure

21 Great Basin Redband Study To address data gaps outlined in the Native Fish Status Review (ODFW 2005). To provide better management for future fishing opportunities. To write effective conservation plans for all Great Basin SMUs. To assess the response of fish populations to changes in climatic conditions.

22 ODFW Redband Trout Study EPA s Generalized Random Tessellation Stratified (GRTS) design - probabilistic surveys - spatially balanced, representative sample 30 sites per basin every year 30 sites per population every 3 years Density estimates at randomly selected sites - 2-pass removal electrofishing Calibrate removal estimates - mark-recapture at sub-sample of sites Collect stream habitat data at each site

23 Land Ownership of Great Basin Redband Trout Habitat Legend Redband Trout Populations Land Ownership Land Ownseship BLM ODF PVT USFS USFWS Kilometers Fort Rock Malheur Lakes Chewaucan Warner Lakes Catlow Valley Goose Lake

24 Sampling Success Warner Lakes, 2007 Site Status ( n = 90) Completed (53) Did Not Survey (1) Access Denied (21) Failed Estimate (2) Dry Channel (13) All SMUs

25 Calibration of Removal Estimates ~ 10 % of sample sites calibrated with mark-recapture techniques. Removal estimates underestimated abundance by 37%, a 0.63 bias. Develop predictive models based on channel complexity and fish attributes. Preliminary analysis of 2006 data show bias correlated to in-stream wood and fish size. 300 Mark-Recapture Estimate y = 1.55x R 2 = Removal Estimate

26 ODFW Redband Trout Study 2008 Site Densities Fish/m (n = 59) (n = 107) (n = 52) (n = 17) High variability Some areas of high density

27 ODFW Redband Trout Study 2008 Site Densities Fish/m 2 Percentage of Sites Cumulative Percent of Sites

28 ODFW Redband Trout Study 60 Blitzen Population Length Frequency 50 n = > 85mm Frequency Dominated by smaller, younger fish High productivity? Fork Length (mm)

29 Occurrence of Brook Trout Legend Brook Trout Redband Trout Distribution Other Streams

30 ODFW Redband Trout Study 2007 population estimates SMU n Estimate 95% CI Catlow Valley 7 24,539 65% Chewaucan ,577 50% Fort Rock 27 70,315 28% Goose Lake ,855 36% Malheur Lakes ,970 37% Warner Lakes ,985 50% Total ,241 22% 2008 population estimates SMU n Estimate 95% CI Catlow Valley Chewaucan ,275 38% Fort Rock 24 39,833 42% Goose Lake 24 36,266 47% Malheur Lakes ,855 19% Warner Lakes ,580 41% Total ,810 19%

31 Age 1+ Fish x Trends in Abundance Fort Rock Goose Lake Chewaucan Warner Lakes Malheur Lakes Year Catlow Valley

32 Population Abundance SMU Population n Estimate 95% CI Goose Lake Drews 20 16,477 69% 2007 Dry 12 2, % Eastside 17 21,613 28% Thomas 21 38,309 58% West Goose 20 41,146 84% Warner Lakes Deep ,565 75% 2007 Honey 17 16,247 60% Twentymile 18 79,808 58% Malheur Lakes Blitzen ,807 36% 2008 East Burns 25 27,940 45% McCoy ,255 35% Riddle 18 45,938 51% Silver 25 41,161 49% Silvies ,074 52%

33 Application of Results

34 ODFW Redband Trout Study - Possible Outcomes - Abundance of redband trout as it relates to stream flow Age 1+ LCT abundance x R 2 = 0.89 p = Mean Annual Precipitation (inches) years i-1 and i

35 300 Mean Annual Flow years i-1 and i-2 Donner und Blitzen River 250 CFS

36 ODFW Redband Trout Study - Possible Outcomes - Changes in Distribution of redband trout relative to climate cycles Wet Dry Fish/m 2 no fish low density high density

37 Redband Trout Density Malheur River, Malheur River North Fork Malheur River Little Malheur River Beulah Reservoir Bully Creek Cottonwood Creek Willow Creek Bully Creek Reservoir Estimated Abundance 298,250 ± 29% Warm Springs Reservoir South Fork Malheur River

38 Migratory Populations

39 Upper Klamath Basin Complex life histories Lake rearing Stream residents Connected Populations Sampling Issues

40 Lost River Klamath Basin Populations Klamath Basin Populations Jackson Creek Rock Creek Williamson River Sun Creek Annie Creek Sycan River 7-mile Cr Sycan River Merritt Creek Spring Cr Sprague River Wood River N. Fk. Sprague River Meryl Cr Williamson River 7-mile Canal 4-mile Cr Cherry Cr 5-mile Creek Rock Cr Snake Cr Trout Cr Crystal Creek 4-mile Cr S. Fk. Sprague River Rock Creek Fishhole Creek Spencer Creek Lost River Rock Creek Klamath River Oregon Rock Creek Fourmile Creek Shovel Creek California Crater Lake Long Creek Cascade Complex Jenny Wood Agency L. U Klamath Lake Klamath River Upper Williamson Lower Williamson Lower Sprague Upper Sycan Lost River 10 Populations 4 Adfluvial MILLER CR JACK CR CRATER L LONG CR SYCAN CR MERRIT CR *C *B *A SPRAGUE R Upper Sprague FISHHOLE CR *B *A WILLIAMSON R ASPEN LAKE GERBER RES JENNY CR TOM CR LOST R LONG PRAIRIE CR FALL CR WILLOW CR WILLOW CR BOGUS CR Rock Creek KLAMATH R

41 Klamath Redband Trends

42 Klamath Redband Genetic Study Better define population structure Mine samples collected in 2000 Also compare with other populations Analyzed by Devon Pearce, NOAA, UCSC 18 microsatellite loci

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44 Klamath Redband Genetic Population Structure Rock Cr, Lower Sprague River Wood River Lower Sprague River Trout Cr, Lower Sprague River Upper Klamath River Lower Klamath River & Jenny Cr Klamath Lake Basin Lost River Scott Cr, central CA coast Goose Lake

45 Movement and Passage of Redband Trout in the Blitzen River

46 Study Location

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48 Blitzen R Diversion Dams Sodhouse Busse Grain Camp Page

49 Objectives 1. Determine movement patterns of fluvial life history 2. Investigate migratory delays at diversion dams

50 Methods Trout caught in traps and by angling Radio telemetry PIT tags Stream temperature and flow Fish scale interpretation

51 Trout Size and Age Distributions Age:

52 Flow CFS Grain Camp Busse Cato Bridge (N = 24) Page Number of trout passing PIT reader Temp ⁰C

53 died

54 Upstream Migration Extent and Arrival Timing

55 Passage Delay at Dams Proportion of trout below dam Busse Busse Grain Camp Grain Camp Page Page Time (days)

56 Stream Temperature Summer 7-day Max Average Temperature ⁰C UILT River km

57 Conclusions Multiple migrations within lifetime Migration not exclusively for reproduction Seasonal migration pattern Spawning had a limited distribution Lack of repeat spawning Lower river trout arrive later at spawning habitat Some dams present passage limitations to trout -Some delayed up to 40 days -Some never pass

58 Conservation Principles for Redband Trout Keys to persistence (Williams et al, 2007): - Protect current strongholds - Increase size and extent of existing populations - Maintain genetic and life history diversity - Reconnect stream systems - Minimize anthropogenic stressors - Improve adaptive management

59 ODFW Conservation Planning Native Fish Conservation Policy Native Fish Conservation Plans Define desired status relative to biological attributes Distribution Survival Describe current status at the population level Abundance Rate of Population Growth Limiting factor analysis including corrective strategies Population Diversity Forecast of Persistence Identify Population monitoring Connectivity and research needs to evaluate success of corrective strategies Include measurable criteria indicating significant deterioration in status & triggering recovery actions

60 ODFW Conservation Planning Native Fish Conservation Policy Native Fish Conservation Plans Collaborative process Technical committee Stakeholder committee Peer review

61 Conservation Planning Challenges for Redband Trout Limited data available Abundance & distribution Lack of long term data sets Lack of sensitivity to detect trend North Malheur Lakes Silvies Conflict in scale at which data are collected Smallest populations aggregated Silver East Burns

62 Conservation Planning Challenges for Redband Trout High among population variability Populations differ in potential Irregular & sporadic monitoring activities Limited opportunities to detect deterioration Few fishery management options for recovery Limited harvest, little or no stocking in running waters

63 Approach Evaluate Populations by Potential Flow - Precipitation & Area Temperature Elevation & Aspect Mean Population Annual Potential Precipitation Malheur Lakes SMU

64 Approach Define desired and current status - Abundance & Distribution Varies by potential Varies by water year High water years Low Water years High Potential Low Potential - 98% of sites with fish - 74% of sites with fish - 50% of sites > 8.1 g/m 2-50% of sites > 0.31 g/m 2-58% of sites with fish - 50% of sites > 0.86 g/m 2-50% of sites with fish - 50% of sites > 0.31 g/m 2

65 Approach Define desired and current status - Reproductive Potential length frequency Population diversity Number of Eco-regions Spatial diversity Habitat heterogeneity

66 Approach Identify habitat related recovery actions Habitat Restoration Restoration of Passage Restoration of instream flow

67 Recent Conservation Actions for Great Basin Redband Trout Harvest impacts are being minimized Creel Survey in Upper Klamath Lake Trout stocking in waters containing redband trout will use only triploid (sterile) trout. Passage and screening in Chewaucan Basin. Screening in Warner Lakes Basin. Collaboration with USGS to analyze redband data to refine population benchmarks (WNTI)

68 Parting Shots Progress over last decade Overall abundant but disconnected and constrained life history expression Uncertainty of what monitoring can be continued Appropriate conservation objectives Effective monitoring strategies Problem of time scale