Discards from mrfss data

[brianlangseth-NOAA]

What is the proper way to pull out discard data from MRFSS. Which fields to use and how?

Some discussion of these in pfmc-assessments/california-data#2

1. Apply prorportion based on fields in MRFSS. In 2021 I used (TSP_HARV) / (TSP_HARV + TSPCLAIM) which gives an approximation of B1 from AB1, but is in numbers.
2. Assume a 42% discard mortality rate...BUT to do this would need amount of discards
3. Look into onbaord discard data....BUT this is for PC and PC is a smaller component of MRFSS landings

[brianlangseth-NOAA]

Asked Budrick this before the Christmas break and he said he would look into it.

[brianlangseth-NOAA]

Also need to follow up on what F_sex = 8 mean

[brianlangseth-NOAA]

Options include

Ratio of B1 in AB1 based on fish observed in numbers (TSP_HARV / TSP_HARV + TSPCLAIM)
Ratio of B1 in AB1 based on estimates in numbers (ESTHARV / ESTHARV + ESTCLAIM)

Here is a figure showing the proportions these values provide:

or apply some proportion based on B2 fish in numbers (TSP_REL or ESTREL)

[brianlangseth-NOAA]

Discussed this with John B. He dug up old MRFSS data that had the original B1, B2, B3 designation and these all showed very minimal discards. Thus the choice of discard calcualtion doesn't have a large impact.

We agreed to used ESTHARV options