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

Recreational fishery length (Figures \ref{fig:wa-lencomp-sexed}-\ref{fig:ca-lencomp-unsexed}) and age compositions (Figures \ref{fig:wa-agecomp-sexed}-\ref{fig:or-agecomp-unsexed}) were obtained directly from \gls{wdfw} and \gls{odfw} and from \gls{recfin} for California. California data included data from the following sampling programs, \gls{mrfss} (1980-2003), \gls{crfs} (2004-2020), and \gls{cpfv} (2003-2020). Lengths from \gls{cpfv} were of fish that were measured prior to their release, i.e., Type 3d data in \gls{recfin}. Even though \gls{wdfw} and \gls{odfw} data are present in \gls{recfin}, state representatives provided data thought to be more reliable than that in \gls{recfin}. Lengths from \gls{wdfw} with the designation of total length (n = 591) were converted to fork length using the conversions of @laidig_lingcod_conversions_1997. Length and age compositions were created for male, female, and unsexed fish, though the number of samples of unsexed, aged fish was small. Many of these composition data lack information on the number of fish sampled out of those landed in a given trip, and therefore, composition data were used without expansion to the sample level. Sample sizes used in the model were based on the number of fish sampled for each year and data set (Tables \ref{tab:sample-size-length} and Table \ref{tab:sample-size-age}). Conditional-length-at-age distributions were also created for Washington and Oregon recreational fleets and explored as a sensitivity.

Measurements from fish designated as released were excluded from the length and age compositions. This led the to the exclusion of 2,920 samples, which was approximately 2 percent of the total samples.

It has been reported that recreational fishers in Oregon sometimes release large fish that are assumed to be female so they can spawn. However, other anglers tend to target and retain these large fish. It remains unclear how this tendency to keep or discard trophy females interacts with minimum size limits. In Oregon, the minimum size limits for r spp have changed between 22 inches during 1995 to 1997 and 2006 to present and 24 inches during 1998 to 2006.

Lengths for the Oregon recreational fishery were available from three sources, \gls{mrfss}, \gls{orbs}, and \gls{odfw} special project sampling. The majority of these samples are from the central Oregon coast (n = 4,440), including Newport (18.7\%), Garibaldi (18.6\%) and Depoe Bay (15.0\%), followed by Brookings on the south coast (n = 2,321; 27.3\%). \gls{mrfss} collected Oregon samples from ocean areas only (n = 8,769) and measured total length from 1980–1989 and fork length 1993–2000. These data have the additional complication of lengths for some fish being estimated from weights instead of direct measurements. These estimated lengths were flagged by \gls{odfw} to allow for selection of directly measured values. However, most imputed weights were conversions from total length to fork length, which do not introduce a great deal of uncertainty. Therefore, all lengths sampled in Oregon from \gls{mrfss} were used to fit the model. Length samples from 2001–2020 from the \gls{orbs} sampling program were in terms of fork length (n =105,197), sampled from ocean trips, and available on \gls{recfin}. Special projects samples collected by \gls{odfw} staff were provided from 2001 (n = 72). These samples were not used to fit the model.

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