In iantaylor-NOAA/Lingcod_2021: Estimate the Status of Lingcod off the US West Coast in 2021

Recreational \glsentrylong{cpue}

Recreational \gls{cpue} time series were abundant for r spp; but, only one index could be added to the stock assessment for each fleet representing state-specific recreational fishing. Some additional time series were provided but not included in the base model. Most often, the longest time series available was included instead.

```{asis, eval = params$area == "North", echo = TRUE, results = "asis"}

Oregon at-sea \glsentrylong{cpfv}

\gls{odfw} initiated an onboard \gls{cpfv} observer program in 2001, which became a yearly sampling program in 2003. The data, 15,632 drifts, were filtered to remove drifts without catches, longer than the 99th percentile, deeper than the 99th percentile (60 fms), and focused on midwater species. Filters were intended to provide a final drift-level dataset free of drifts that were unlikely to encounter r spp. Low sample sizes also necessitated the removal of 2020 and drifts from February. The final dataset included 8472 drifts, 46\% of which encountered r spp.

Bayesian delta-\gls{glm} were fit using rstanarm. Catch (number of retained and discarded fish) with an offset for effort (angler hours) was best fit using a negative binomial model. Investigated covariates included year and two-month wave, port, and depth. Depth was defined as the starting depth for the drift and binned to five fm bins from 0 - 30 fms with a plus 30 fm bin for all drifts with a starting depth > 30 fms. Year and port interactions were not considered. Based on \gls{aic}, no covariates were excluded from the analysis.

Posterior predictive checks of the Bayesian model fit for the negative binomial model were reasonable. The negative binomial model generated data sets with the proportion zeros similar to the 54\% zeroes in the observed data. The estimated time series had a trend similar to the arithmetic mean of the annual \gls{cpue} and the Oregon recreational \gls{cpue} derived from the \gls{orbs} data set (Figure \@ref(fig:fig-Dnbin-marginal-ORAtSea)). ```

\glsentrylong{crfs}

\gls{crfs} samples private boats in the California recreational fishery dockside. Number of r spp per number of anglers is available as well as distance fished from shore, county, port, interview site, year, month, and district. Data on private boats using hook-and-line gear provide a proxy for recreational \gls{cpue}. Currently there is no way to include multiple indices for the California recreational fleet and time did not allow for inclusion of this index as a sensitivity.

Fin rays from \glsentrylong{cdfw}

The \gls{cdfw} collected r utils_name("common") fin rays from the commercial and recreational fisheries in recent years and cleaned them in preparation for ageing. Sampling occurred from February through June 2019 between Crescent City and Santa Barbara, California. Samples were aquired for priority species, not just r utils_name("common"). In total, 113 r utils_name("common") fin rays were collected. The majority of samples were landed utilizing hook-and-line gear, though some trawl-caught samples were also obtained. Meta data for these samples includes port of landing, gear type, length, weight, sex, and maturity.

Unfortunately, restricted access to ageing laboratories because of the COVID-19 pandemic made it nearly impossible to finish ageing even routinely-aged collections. Sectioning and mounting the fin rays typically requires a hood and ventilation, which limited the options for alternative laboratory space. The fin rays collected by \gls{cdfw} are adequately preserved and can still be aged at a later date allowing for future exploration of this data source.

In 2017, \gls{cdfw} began opportunistically collecting filleted groundfish carcasses from the recreational fishery to increase recreational biological data. Samples were collected in a partnership with \gls{cpfv} operators and at public fillet stations, launch ramps, and piers. Current efforts have been primarily focused in the Crescent City and Monterey Bay port complexes as well as samples from south of Point Conception in collaboration with the Sportfishing Association of California, yielding a total of 324 r utils_name("common") fin rays. In addition to age structures, meta data includes port of landing, carcass length, and sex when it can be determined from the filleted carcass. A graduate student at California Polytechnic University, San Luis Obispo is working on a study of total length to carcass length for recreational species, including rockfish and r utils_name("common"), results of which will help inform the best treatment of length information attained from carcasses. These samples could be included in future assessments potentially as conditional age-at-length compositions or as marginal compositions. Both types of data are helpful for estimating growth and selectivity patterns.

iantaylor-NOAA/Lingcod_2021 documentation built on Oct. 30, 2024, 6:42 p.m.