Assessing the Population Structure of the Southern Brown Shrimp Farfantepenaeus subtilis (Pérez-Farfante 1967) Using Different Sampling Methods

10.54451/PanamJAS.19.1.6

“…Morphometric relationships are important tools that help understanding essential biological aspects of populations of aquatic organisms. Allometry of growth from length-length relationships has been used to understand ecology and reproductive changes in several crustacean species, such as in crabs (e.g., Bertini et al 2007 and shrimps (e.g., Rosa et al 2021, Reis-Júnior et al 2023, where the analysis of the slope of these relationships are directly linked for example to energy investments during the reproductive processes. In addition, estimating weight from size is important in ecosystem modeling, especially when only length data is available and estimating biomass is required (Kimmerer et al 2005).…”

“…The four shrimp species analyzed here were found in both types of samples: shrimp + bycatch (in Pirambu) and separated into size categories (in Aracaju). For more details of the sampling procedures used in this study, see Freire et al (2020) and Reis-Júnior et al (2023). All samples were frozen and stored in the Laboratório de Ecologia Pesqueira -Departamento de Engenharia de Pesca e Aquicultura -Universidade Federal de Sergipe (LEP/DEPAQ/UFS) for further analysis.…”

“…Finally, for S. dorsalis, the morphometric relationships presented here were the first to be estimated. Growth allometry in TL-CL relationships for shrimps has been associated with differential metabolism between juveniles and adults (Dall et al 1990), where juveniles have steeper slopes due to higher metabolism (see difference between juveniles and adults in Farfantepenaeus subtilis in Reis-Júnior et al 2023). Another characteristic evaluated is usually the difference between sexes.…”

“…Females tend to direct part of the energy investment into the reproductive process, a process known as 'reproductive drain', which makes it possible to observe differences in allometry when compared to males (Dall et al 1990, Reis-Júnior et al 2019, 2023. The weight-length relationships follow the same pattern: even though the sex differences in allometry for the parameter b is well-known and associated with differentiated reproductive investment (Leite-Jr & Petrere-Jr 2006, Reis-Júnior et al 2023, it is also possible to observe a monthly variation in b for some species (see, e.g., Xiphopenaeus kroyeri in Reis-Júnior et al 2019) and an annual variation, suggesting changes in competition for food resources in these populations (see Rimapenaeus contrictus in Oliveira-Souza & Lavrado 2017). Pauly et al (2022) added a new element to this discussion, stating that limiting oxygen for water breathing organisms, including crustaceans, may be the most limiting factor responsible for some of observed sexual differences (known as the 'gill oxygen limiting theory' or simply GOLT).…”