Caracterização da pesca e aspectos biológicos do camarão de água doce Macrobrachium rosenberguii (De Man, 1879) no município de Chaves-Pará.

Abstract

In this study, we present the characterisation of fishing and some biological data on the invasive shrimp Macrobrachium rosenbergii (De Man, 1879) collected in Vila Canivete, in the municipality of Chaves/PA. The shrimp were collected over a period of one year, but the species M. rosenbergii was only caught between July 2021 and March 2022. To catch the shrimp, the fishing tools used were matapi, with an opening of 0.5 cm, and tarrafa, with an opening of 1 cm between the knots, always using babassu as bait. The abiotic data temperature and salinity were measured during the study. The temperature remained practically constant throughout the period, ranging from 27.6 to 28.1 oC, and salinity varied from 0.1 in the rainy season (December and March) to 0.7 o/oo in the period with little rain (July to November). In the laboratory, the individuals were identified, sexed, measured and weighed. In this study, 179 individuals were captured. The total number of females (72 animals) captured throughout the period was lower than the number of males (107 animals). In terms of average total length and total weight, the males had higher numbers than the females. Of the 107 females caught during the research period, 34 (47.2 per cent) had no eggs, while 38 (52.8 per cent) had eggs. Regarding the number of females of the species M. rosenbergii by month, it was possible to observe that there was a predominance of ovigerous females in most months, except for October 2021 and January 2022. The occurrence of maturing females was observed in all the months in which they were caught, although in the rainy months (December and March) there was a higher occurrence. The population of Vila Canivete, in the municipality of Chaves/PA, actively uses M. rosenbergii in their economic activities and subsistence consumption. However, the presence of an invasive species in the environment causes serious damage to the ecosystem. This makes it necessary to create management plans and control the invasion of M. rosenbergii in the Amazon province, in order to preserve the natural environment and the integrity of native species in the environment. In addition, it was found that M. rosenbergii shrimp fishermen need public policies to promote educational and fishing activities, as well as the generation of employment and income, in order to improve the quality of life of the local population.