Technical Memo #1 Estimation of Returns of Naturally Produced Coho to the Klamath River

1. Cramer Fish Sciences Technical Memo #1Estimation of Returns of Naturally Produced Coho to the Klamath River Nicklaus K. Ackerman Brian Pyper Ian Courter Steve Cramer

2. Tech Memo 1 Objectives: • Develop basin-wide estimates of run size to populate the initial brood cycle in the model. • Develop population/reach escapement estimates for recent broods to allow partitioning of the coho run throughout the basin. • Use run size estimates and partitioning system as reference points for future validation of model results.

3. Tech Memo 1 Method 1 – Harvest Sampling Approach: • Used captures of TRH origin and natural origin coho in Yurok Tribal Fishery, at WCW, and at TRH to estimate basin-wide run size. Evaluated 1999-2005. Method 2 – Tributary Approach: • Used best available information from individual populations/reaches to approximate run sizes in different portions of the basin. Evaluated 2001-2004.

4. Coho Enter River from Estuary in Late Summer - Fall Harvest Sampling Approach Trinity River Hatchery Iron Gate Hatchery Natural

5. Yurok Tribal Harvest Sampling Tells Us Proportions of TRH, IGH, and Natural Fish In Estuary and Lower River Harvest Sampling Approach Trinity River Hatchery Iron Gate Hatchery Natural

6. WCW Tells Us Natural:TRH in the Trinity Harvest Sampling Approach Change in TRH:Natural Ratios From Estuary to WCW Tells Us the Proportion Of Natural Fish in Estuary Moving Here CDFG Abundance Estimates in Trinity Allow us to Estimate Basin Run Size Trinity River Hatchery Iron Gate Hatchery Natural

7. Harvest Sampling Approach Passage Timing of Coho at WCW 2005 WCW Removal 1999, 2000 WCW Removal 1998, 2001-04 WCW Removal

8. Harvest Sampling Approach

9. Harvest Sampling Approach Harvest Timing in Yurok Tribal Fishery, 2000-2005

10. Tributary Approach Estuary - Trinity

11. Tributary Approach Klamath Coho Life Cycle Model Reaches: Williams et al. (2006) Historically Independent Populations: Lower Klamath River Middle Klamath River Upper Klamath River Shasta River Scott River Salmon River Upper Trinity River Lower Trinity River South Fork Trinity River Lower Klamath River* Middle Klamath River* Upper Klamath River* Shasta River Scott River Salmon River Trinity River *Mainstem and Tributaries are modeled seperately so that we may test effects of mainstem water management.

12. Tributary Approach Objective:Use the data available to generate rough estimates of abundance for each model reach. Method Limitation:Diverse suite of methods used inhibits comparison of estimates between reaches.Compounding assumptions affect accuracy and certainty around resulting estimates. Benefits:Provide approximations of run size where estimates were previously not available. Highlights areas where improved monitoring would be beneficial.Sum of estimates for reaches is useful for comparison to Harvest Sampling Approach estimates.

13. Tributary Approach Primary Data: Upper Klamath Mainstem Middle Klamath Mainstem Lower Klamath Mainstem Middle Klamath Tribs. Upper Klamath Tribs. Shasta River Scott River Salmon River Trinity River Lower Klamath Tribs. 2001-2005 Mainstem Spawning Surveys Professional Judgement 2004 Bogus Creek Counts Shasta run timing and IGH entry timing Accounting of habitat availability 01-04 Shasta Counting Facility Counts 01-04 Redd and carcass counts 03-04 Spawning surveys WCW Population Estimates Regional Juvenile Abundance Estimates Model Reach:

14. Tributary Approach 2003 Passage Timing at Shasta Counting Facility 2002 2003 2001 2004

15. Tributary Approach

16. Tributary Approach * Modified from Tech Memo to reflect that some spawners will be assigned to the reach.

17. Run Size Estimates