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[redside1]

to protect upper Fraser chinook stocks.
Somehow they think the catch and release fishery had 4,000 moralities on upper Fraser Chinook stocks.
When only 14,500 returned I doubt the sport fleet caught and killed another 4,000pcs of those particular stocks.

https://watershedwatch.ca/media-releases/federal-government-measures-failed-to-protect-endangered-chinook-salmon-in-2019/

[Rodney]

I'm a little puzzled by how the number 4,000 is determined. The problem with these press releases by individual organizations, doesn't matter if it is environmental, sport fishing, commercial fishing, etc, is that they put out a generalized statement with no reference and are legitimized by "recent analysis...". The public, with no particular interest in digging further into it, accept the numbers and follow the agenda if they get fired up enough about it.

Today I was invited to Dr Scott Hinch's Pacific Salmon Ecology and Conservation Laboratory at UBC for his annual symposium where his students and colleagues present their studies this past year, mainly on salmon management. The presentations were from 9am to 4pm, but quite refreshing to listen to research results being presented in details and have actual intellectual conversations on the subjects. It makes you appreciate the amount of collaborative work which is going on behind the scene while the stakeholders are publicly lashing out on each other.

I won't go into details on what the presentations were today, because they're quite complex and lengthy. I will be putting together a couple other posts later on, most likely on Facebook, to summarize these studies and findings. The most interesting one from today, which is pretty related to the topic of this thread, is the effects of catch and release on migrations of marine chinook salmon. I was quite blown away by the methodology and the results. Another good one was the effects of (Fraser River) fisheries (gill and seine net) entanglement on sockeye salmon's gene expression, infection and offsprings. There was also a presentation on Big Bar rockslide, more detailed than what was presented to me at the last SFAC. Also, the study on the movements and habitat use of juvenile salmon in the Fraser estuary fascinated me, because firstly I knew very little about it, secondly the studies took place at locations where I used to fish and gave me a better understanding on bull trout feeding behaviours.

[stsfisher]

This is the "backgrounder" attachment. Whole lot of "assumptions" made based on speculation numbers from what I read.

https://watershedwatch.ca/wp-content/uploads/2020/02/Backgrounder-The-2019-Fishery-on-Endangered-Fraser-Chinook.pdf

[wildmanyeah]

Today I was invited to Dr Scott Hinch's Pacific Salmon Ecology and Conservation Laboratory at UBC for his annual symposium where his students and colleagues present their studies this past year, mainly on salmon management. The presentations were from 9am to 4pm, but quite refreshing to listen to research results being presented in details and have actual intellectual conversations on the subjects. It makes you appreciate the amount of collaborative work which is going on behind the scene while the stakeholders are publicly lashing out on each other.

Greg Taylor

Below is a better description of our methodology. It was presented in a poster at the UBC Salmon Migrations Workshop today.

I think the key points being missed in this discussion are (1) these Chinook CUs have been classified as Endangered or Threatened by COSEWIC and (2) the Minister committed to an objective of 5% total mortalities in 2019.
Our objective was to determine what the total mortalities were relative to this objective. There were only 3 of 10 potential fisheries with any reasonable data. The SC recreational fishery was one.
If you read the report below we clearly say we don’t know the ‘real’ number of total mortalities in the south coast recreational fishery. We provide estimates using DFO, PSC, and Patterson et al, 2017.
We can all agree the total mortalities were not zero. We came up with an estimate of 3,494. Is this number ‘right’? As we say in the report, it will require better monitoring of stock composition, research, and information from the recreational community to refine the number to something most are reasonably comfortable with.
But the more difficult issue is, if we need to limit mortalities to 5% on these Endangered Chinook, which is around 1,800 Chinook, how should it be done? Especially considering the south coast fishery is only one of many fisheries which encounter these populations.
I know you don’t want my advice, but here it is. Demand genetic monitoring of both retained catch and releases, develop a mechanism to independently evaluate catch, releases, and compliance in your fishery, work with SFI and researchers to gather information that would reliably inform Patterson et al, 2017’s Risk Factors, and support further research on the long-term consequences of catch and release.
None of this ensures your fishery. God knows, I have done all of the above in commercial fisheries only to see managers close them anyway.
But it gives your industry the right to say your fishery is managed and prosecuted to the highest international standards of fisheries management. It will also give you the power to refine your fishery.
In terms of the concern expressed that there other fisheries which impact these CUs, I agree.
Here is the report I mentioned:

https://www.mccpacific.org/wp-content/uploads/2020/02/Backgrounder-The-2019-Fishery-on-Endangered-Fraser-Chinook-copy.pdf

https://www.mccpacific.org/wp-content/uploads/2019/03/Fraser-Chinook-FRIM-Discussion-Paper_6-March-2019.pdf

[wildmanyeah]

They use a 37% catch and release mortality rate for chinook fishery based on this

In Patterson et al. (2017b), guidance is given through risk factor scoring tables. We used these tables as
well as local knowledge of recreational fisheries to inform our selection of FRIM mortality ranges for the
simple Excel spreadsheet and the stochastic modelling work. One suggested formula for the calculation
of FRIM is from the PSC as referred to in Patterson et al. (2017b):
𝐹𝑅𝐼𝑀 = (𝐾𝑒𝑝𝑡 𝐶𝑎𝑡𝑐ℎ 𝑥 𝑃(𝑁𝐶𝑀) + [𝑅𝑒𝑙𝑒𝑎𝑠𝑒𝑑 𝐶𝑎𝑡𝑐ℎ 𝑥 (𝑃(𝑁𝐶𝑀) + 𝑃(𝑃𝑅𝑀))] (2)
Where 𝑃(𝑃𝑅𝑀) = 𝑃(𝐶𝑎𝑝𝑡𝑢𝑟𝑒 𝑀𝑜𝑟𝑡𝑎𝑙𝑖𝑡𝑦) + 𝑃(𝐻𝑎𝑛𝑑𝑙𝑖𝑛𝑔 𝑀𝑜𝑟𝑡𝑎𝑙𝑖𝑡𝑦) + 𝑃(𝐼𝑛𝑗𝑢𝑟𝑦 𝑀𝑜𝑟𝑡𝑎𝑙𝑖𝑡𝑦) +
𝑃(𝑃𝑟𝑒𝑑𝑎𝑡𝑖𝑜𝑛 𝑀𝑜𝑟𝑡𝑎𝑙𝑖𝑡𝑦)
This separates mortality into a non-capture mortality rate (P(NCM)) and post-release mortality (P(PRM)).
For the rest of this paper, NCM will be referred to as drop-out mortality (P(DOM)).
The range of the probabilities for the four sub-components of Post Release Mortality (PRM) estimates
were drawn from the Table 1. The Risk Factors and Mortality Risk Ranges are taken from Appendix A in
Patterson et al. (2017b). The chosen Mortality Risk Range was based on selective interviews with two
experienced anglers: one an experienced guide, the other a retired biologist who fishes non-guided. We
could not find any published fishery independent or dependent estimates of the Risk Factors and
mortality ranges.

[wildmanyeah]

This is the "backgrounder" attachment. Whole lot of "assumptions" made based on speculation numbers from what I read.

https://watershedwatch.ca/wp-content/uploads/2020/02/Backgrounder-The-2019-Fishery-on-Endangered-Fraser-Chinook.pdf

Its a lot of assumptions IMO the 37% mortality form Catch and Release is pretty damn high from other science I have read but beacuse the intercepts from catch and release were so low on these stocks they had to bump up the mortality to prove their point.

we seem to be in the time of just shut down everything

[wildmanyeah]

2.7 Assumptions

1. DNA data from 19/20 can be expanded to cover all areas.
a. This is an obviously data limited simplistic approach. It is highly likely that there are
differences in the stock composition in each area, and in the timing of the chinook
present as they move through their migration

2. DNA data in released catch approximates the samples from the kept catch.
a. This is likely not true in areas and times where slot sizes management measures exist.
This concern is hypothetically addressed in the management scenario section (2.6.1)

3. Actual DNA data in 2018 is represented by the average of all years with DNA data (2009, 2010,
2014, 2016 and 2017).
a. Actual 2018 DNA data will be available shortly. There is considerable variation in DNA
proportions of Fraser River 42/52 in June which will affect the analysis if 2018 DNA is
different than the mean

4. DNA sampling rates are adequate to estimate representation by stock components of interest.
a. Efforts should be made to increase the sample size, however uncertainty of DNA
estimates could easily be incorporated into the model

5. Uniform distributions approximate the true distribution of mortality parameters.
a. Triangular, normal or other distributions can easily be used if future work shows that
they are more appropriate distributions

6. There is no error in the catch and release data.
a. This could be addressed by providing a normal distribution around the kept catch and
released catch estimates

7. Potential differential impact of high Fraser River water temperatures on released chinook versus
non-encountered chinook are not incorporated.
a. Additionally, Fraser River water temperatures would be expected to increase PRM
estimates in areas where releases occur much closer to the Fraser River (e.g. Area 29)

8. Compliance with regulations.
a. Uncertainty regarding compliance with fishing regulations, slot size restrictions, and
catch reporting requirements in a fishery with low levels of enforcement and no fishery
independent monitoring

[RalphH]

The Patterson et al (2017) paper on FRIM:

https://www.fecpl.ca/wp-content/uploads/2017/05/CSAS-FRIM-RESDOC-A-2017_010-eng.pdf

I scanned it only but it looks at all fishing methods including commercial troll gill net etc. It's based on a meta-study - review of previously published material plus communication with authors of those papers.

So it does not focus exclusively on angling.

[wildmanyeah]

They got to the 37% by using the tables in that study.

They also used this type of information to come to conclusions

"The range of the probabilities for the four sub-components of Post Release Mortality (PRM) estimates were drawn from the Table 1. The Risk Factors and Mortality Risk Ranges are taken from Appendix A in Patterson et al. (2017b). The chosen Mortality Risk Range was based on selective interviews with two experienced anglers: one an experienced guide, the other a retired biologist who fishes non-guided. We could not find any published fishery independent or dependent estimates of the Risk Factors and mortality ranges."