Octopus sp. fishing on the coast of Cuajiniquil, Guanacaste, Costa Rica

In Cuajiniquil, North Pacific of Costa Rica; Octopus sp. through diving and the fishing gear called "hook", however, this resource has not contacted the necessary measures for sustainable management. The objective of the research is to provide biological information about Octopus sp. that allows a sustainable use in Costa Rica. Monthly samplings were carried out for six months between May 2018 and March 2019 of Octopus sp. with the help of the artisanal fleet in the study area. The following biometric parameters were determined: weight (g), the dorsal length of the mantle (cm), total length (cm) and width (cm). Sex was identified through the presence / absence of hectocotyl and the length-weight relationship was obtained. There are only determined differences in the width (cm) of the organisms according to sex (p < 0,05), the sex ratio without different differences (p=0,05), and the height-weight relationship turned out to be negative allometric for both sexes. Statistically (p < 0,05) the smallest sizes of organisms were identified in the rainy season, specifically November. The fishing gear used is not selective, the data showed that organisms of smaller sizes than those established and recommended in the literature are being removed. In a possible management plan, it is recommended not to extract organisms in the month of November because there is a high presence of juvenile organisms and it is required to establish sustainable extraction measures.