Just thought I'd toss this in for JimB to help get a better understanding of what #'s were really happening in Cedar Creek. It kind of walks on Gary's story......
Here is a really interesting comparison that pits Cedar Creek coho productivity against the hatchery facility directly across from its mouth. The new info is in bold at the end of each broodyear’s description.
Cedar Creek Brood Year 2003/Run Year 2006 Adult Production and Return
WDFW estimated the total Cedar Creek coho smolt production at 58,174. The juveniles smolted in the spring of 2005.
http://wdfw.wa.gov/fish/wild_salmon_...g-rpt_2005.pdfPage 92 of your reader.
WDFW coded wire tagged about 26,000 which again is a tag rate of just about 1 in 2.
http://www.rmpc.org/reports/RBA691.txt5 CWT’s were recovered from this tag group in 2006. 4 were recovered in 2006 CR gillnet fisheries. 1 was a hatchery recovery.
http://www.rmpc.org/reports/TS1-Run1207.txtRMIS reports these 4 tags expand to 5 for fishery sampling sizes.
The tag rate for the total 2003 brood year smolt production in Cedar Creek was about 1 in 2.
The Lincoln-Petersen mark and recapture principal would then dictate to us the CR gillnet fleet harvested 8 Cedar Creek Coho (multiply the estimated tags by 2 to account for the smolt tag rate of 1 in 2). By the spawner tables linked above anyone can see that the balance of the 16-32K adults did not show up in Cedar Creek as spawners in 2006.
Now........let’s compare this to the hatchery facility right next door to Cedar Creek.
Take a gander at what the happens when you leave hatchery fish at the hatchery.
Here are the tag recovery tables with adult production estimates (the EST’d column represents the total adult production estimate) for the Lewis River Hatchery (directly across from the mouth of Ceadr Creek) coho smolt releases for the exact same broodyear and adult return year.
http://www.rmpc.org/reports/TS1-Run20016.txtJust look at it. You have hatchery production smolt release groups, just barely larger than Cedar Creek’s smolt production, producing between 1,500 and 2,000 adult recruits and these release groups do it with fewer than 100 adult spawners. Cedar Creek uses thousands of adult spawners in the form of hatchery production adults spawning naturally combined with hatchbox releases and in turn produces virtually no adult recruits.
And check out the number of adults that escaped all fisheries and converted to spawner broodstock! Just look at what percentage of the adults escaped all fisheries, including the curtains of death, and became available for spawning. Nearly 70% of the adult recruits became spawners.
Now let’s compare broodyear 2002 Cedar Creek coho to the Lewis River Hatchery coho the year before......
Cedar Creek Brood Year 2002/Run Year 2005 Adult Production and Return
The total coho smolt production based on the Lewis River Hatchery inputs plus the Cedar Creek no ad-clip hatchery hatch box coho into Cedar Creek was pegged at about 34,999 by WDFW. It was an intense estimation effort complete with juvenile trap efficiency tests to assure the highest level of certainty around the estimate.
Page 83 of your reader.
http://wdfw.wa.gov/fish/wild_salmon_...heececarcr.pdfThe no ad-clip hatchery hatch box coho produced 1,970 of the total smolt production based on the otolith sampling (the eggs transferred to the hatch boxes had their earbones thermally marked at the hatchery in order to determine their contribution to the streams overall productivity).
Finally, a group of slightly under 17,000 coho smolts from the total of 34,999 received a coded wire tag. The tag rate then is then just about 1 in 2. In other words, for every 1 tagged smolt there exists 1 smolt from the Cedar Creek smolt production that does not possess a Cedar Creek tag.
Here are the two tag code groups from Broodyear 2002. They were trapped and tagged in Cedar Creek during the juvenile out migration season of 2004.
http://www.rmpc.org/reports/RBA17991.txtNow, this CWT group represents smolt offspring from hatchery coho spawning naturally in Cedar Creek (because the Lewis Hatchery is directly across from the mouth of Cedar Creek), first generation hatchery progeny adults that produced offspring, other generations of hatchery progeny adults that produced offspring combined with the Fish First no ad-clip hatchery hatch box coho.
While the coded wire tags couldn’t be implanted into just the Fish First no ad-clip hatchery hatch box coho, the general Cedar Creek wild spawned hatchery coho smolt-to-adult survival rates and the Cedar Creek ocean and LCR fishery exploitation rates can now be determined.
This Cedar Creek coho brood year life cycle can now be described from cradle to grave.
The RMIS database is web based. It allows one to access all tag recoveries in addition to tagged groups and ad-clip release summary. This RMIS program is the database store and clearinghouse for CWT research on the west coast (including Canada via the Pacific Salmon Treaty).
http://www.rmpc.org/Here are the adults that were generated from the two brood year 2002 tag groups. The point estimate is 22 adults.
http://www.rmpc.org/reports/RBA17991.txthttp://www.rmpc.org/reports/TS1-Run19730.txtIn 2005 16 adult Cedar Creek coho CWTs were found in all west coast salmon fisheries. This sample is reported by RMIS to expand to an estimated 22 Cedar Creek CWT’s (total harvest is rarely sampled for either recreational or commercial fisheries so it must be expanded to match the landings). There are three tags that have no EST’d number so we will just add their raw numbers to the 22 for a total of 26 estimated fishery tags.
Based on the Cedar Creek smolt tag-to-no tag ratio one can assume 52 adult coho (smolt tag rate multiplied by the estimated adult production fishery tags) from Cedar Creek were taken by all non-ad-clip retention west coast salmon fisheries(the CR gillet fishery is a component of this). The recreational fleet operating in the ocean and B10 usually has half the impact allocation so another 52 can be assumed dead in those fisheries (just not retained due to ad-clip only regulations).
104 adults (non ad-clip fisheries plus ad-clip fisheries) were generated from the entire 2002 Cedar Creek brood year spawners combined with the hatch boxes.
According to the spawner tables linked above, 231 no ad-clip adult coho produced from brood year 2002 ran into Cedar Creek in 2005. Just for good measure let's add these to the adult production we see from the tag recovery table. We will assume none of these no ad-clip adults are the result of the Lewis River (or other CR basin no ad-clip hatchery releases) no ad-clip hatchery juvenile releases. Let’s just assume they are all the result of a natural spawn in Cedar Creek.
104 + 231=335 adults produced off the 2004 smolts resulting from the brood year 2002 spawn in Cedar Creek.
335 x 0.05(the no ad-clip hatch hatchery hatch box coho contribution to smolt production as reported by WDFW in the linked report above) = 16.75 adults that were produced from 400,000 hatchery eggs.
16.55 adults were produced from 400,000 hatchery eggs incubated in the SRIs.
To compound matters further, based on the adult spawners needed to create the adult recruits from the Cedar Creek no a-clip hatchery hatch box coho, the project is exhibiting an adult recruitment rate in the neighborhood of 0.05 adults per spawner.
It is quickly obvious the 16-32K adult claims did not occur off the brood year 2002 production.
Now look at this........
Here is the tag recovery table that shows all the Lewis River Hatchery coho adult recruits from the exact same broodyear.
http://www.rmpc.org/reports/TS1-Run21195.txtJust look at that adult production! Less than 100 adult spawners (based on 2,000 eggs per coho female) per smolt release group turned around and produced up to almost 2,300 adult recruits.
Once again look at the massive spawner escapement! With nets and recreational fishing combined!
Keith
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