Evaluating Stock Status and Biological Reference Points for a Data-Limited Brown Shrimp Fishery in the Gulf of California Data-Limited Assessment of the brown shrimp fishery in the Gulf of California

The state of exploitation of the brown shrimp,Penaeus californiensis, fishery in the northeastern region of the Gulf of California was evaluated using landed catch and fishing efforts from 2010 to 2020. The annual catchability coefficient, 𝑞_𝑦, was estimated through the Leslie model; the monthly biomass, 𝐵_𝑚, was estimated from the catch per unit effort; 𝑈_𝑚via the relationship 𝐵_𝑚= 𝑈_𝑚/𝑞_𝑦; and through a biomass accumulation model throughout the fishing season, an approach to the biomass corresponding to the carrying capacity, 𝐵_∞,𝑦, was obtained. The harvest rate, 𝐻𝑅, for each month and year was obtained and the annual maximum sustainable yield, 𝑀𝑆𝑌_𝑦, derived as 𝐻𝑅_{𝑀𝑆𝑌,𝑦}= 0.50, which represents the target biological reference point, 𝐵𝑅𝑃_𝑡𝑔𝑡. The decrease in population abundance allows for estimates of the recruitment rate, 𝜌_𝑦, at the beginning of the fishing season and the survival rate, 𝑠_𝑦, at the end of the fishing season, which represent the remaining reproductive population. From these estimates, a limit biological reference point was computed, described as<inline-formula><inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="658454v1_inline1.gif"/></inline-formula>, which corresponds to the population replacement level. With these estimates, the Kobe diagram was constructed, in which the biological reference points 𝐵𝑅𝑃_𝑡𝑔𝑡and 𝐵𝑅𝑃_{𝑙𝑖𝑚,𝑦}were incorporated. The diagnosis of the state of exploitation indicates, considering a precautionary criterion regarding recruitment, that the fishery has been operating at acceptable levels of sustainability, near the maximum production capacity.