Compile Data - Discards

[brianlangseth-NOAA]

2. Discards

• [x] WCGOP
  • [x] Have discard estimates from chantel as of 1/27 and now save on drive UPDATE (2/15) commit fab41ac adds file to apportion GEMM discards by state, and commit ffd23c0 includes updated 2016 data and produced final values
  • [ ] Discard length estimates from andi as of 2/9. Need to analyze
• [x] Rec
  • [x] WA - will need to come up with discard mortality rate UPDATE (2/1) Have releases by depth. This Council document has discard mortalities by depth at the surface - Table 1-10 for rec hook and line. No estimates of descender device use so Table 1-13 not useful. UPDATE (2/9) Added discards in commit fadacff UPDATE (4/27) Obtained estimates of descender device usage from 2016-2022 from Erica Weyland. Added these alongwith values from Table 1-13 to update discard for WA rec in commit f55b2fa
  • [x] OR - discards included
  • [x] CA - can use from recfin. See discussion here about MRFSS having discard information

Other sources?

• [x] Historical commercial was based on assumed rates. Data to inform those rates were from Pikitch studies for 1981-1994. Jim Hastie has email about that data (sent 2/1) and John Wallace would be the contact to see if that changes as fleet structure changes. UPDATE (3/6): John replied to this and confirmed similar estimates as in last assessment (5%). Plan to use 1% <1981 and 20% 1995-199.

[brianlangseth-NOAA]

Chantel has added the latest Groundfish Mortality Report onto our network here:

\nwcfile\FRAM\Assessments\GEMM Report\GMR_2021

where the GEMM data are in table 3 in the excel file.

These can also be accessed by using the nwfscSurvey package which includes a function to pull these data (thanks to Erin Steiner) from the data warehouse:

widow_data <- nwfscSurvey::pull_gemm(common_name = "Widow Rockfish")

Currently, the most recent GEMM data from 2021 is not in the data warehouse yet but should be available soon.

[brianlangseth-NOAA]

For discards for commercial samples, email Andi/Chantel and they will provide csv's to make the calculations. These data will be available after december.

[brianlangseth-NOAA]

When have commercial fleet structure known, and have NDA's signed, send request to Chantel/Andi via this form data request form

[brianlangseth-NOAA]

Sent request based on planned fleet structure of trawl and non-trawl gears

[aliwhitman]

With the OR recreational catch, RecFIN has estimated discards in mt and so I was planning on providing the recreational total mortality but with retained and discard dead estimates separately (2001 - 2022). I also did not recommend estimating discards during the "historic" period prior to 2000 (bag limits were high! discarding was very limited).

Just wanted confirmation prior to sending.

[shcaba]

That sounds good to me.

On Wed, Jan 25, 2023 at 9:26 AM Ali Whitman @.***> wrote:

With the OR recreational catch, RecFIN has estimated discards in mt and so I was planning on providing the recreational total mortality but with retained and discard dead estimates separately (2001 - 2022). I also did not recommend estimating discards during the "historic" period prior to 2000 (bag limits were high! discarding was very limited).

Just wanted confirmation prior to sending.

— Reply to this email directly, view it on GitHub https://github.com/pfmc-assessments/canary_2023/issues/10#issuecomment-1403977830, or unsubscribe https://github.com/notifications/unsubscribe-auth/AB6IZLXQ7EXPIXHPB6EA4ATWUFO4FANCNFSM6AAAAAAQUMHX2Y . You are receiving this because you are subscribed to this thread.Message ID: @.***>

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Jason M. Cope, Ph.D.Research Fishery Biologist Fishery Resource Analysis and Monitoring Division Northwest Fisheries Science Center 2725 Montlake Blvd. East

Seattle, WA 98112-2013 NOAA Fisheries Affiliate assistant faculty School of Aquatic and Fishery Sciences University of Washington @. @.> (206) 302-2417 www.nmfs.noaa.gov

[brianlangseth-NOAA]

Confirmed @aliwhitman. Having both separated will be helpful.

If we are wanting to model discard rates in the recent period, presumably that could be obtained by dead discard over the sum of dead discard and live discard, which could be provided separately if we use it. I think for now, what you plan is great.

[brianlangseth-NOAA]

@chantelwetzel-noaa mentioned that because we are planning on adding discards to landings, the GEMM report estimates of total discards will likely be a better estimate (because the expansion is more fine scale) of total mortality than calculating discards as the product of rates from the WCGOP data and landings from PacFIN. I plan to look at both to ensure they are in the same ball park (they should be)

[okenk]

Accord to the latest SSC accepted practices document, "STATs should include an analysis to evaluate whether there is evidence of size-based discarding and determine if the assessment model should include size-based retention for either commercial or recreational catch."