By Leticia Marisol Talavera and Luis Fernando López

Fishing is one of the most important economic activities of our country and by 2016 contributed an estimated of 35 billion of pesos (Notimex, 2017), this is a historical amount, with a tendency to increase.

Baja California, specifically, occupies the third place at a nationwide with 10% of the national production (Martinez, 2018). Cedros Island, El Rosario, Valle Tranquilo and San Quintín are some of the most important sites of the region, since organisms of highly economic value are captured here, such as abalone, shrimp, lobster, urchins, tuna and octopus (SEPESCA, 2015).

In Baja California there are two octopus species of commercial interest: Pacific red octopus (Octopus Rubescens) and the Verrill’s two-spot octopus (octopus bimaculatus), the latter is the most commonly fished, and the Pacific red octopus has also been seen as a potential fishing resource for the region (SEPESCA, 2015).

These animals are distinguished from other mollusks by the absence of an external shell, their rounded body, and the cephalic region is attached to eight arms with suckers. Likewise, they are capable of changing their color in dangerous situations (Pliego-Cárdenas, 2009; Guzmán-García et al., 2017).

The Verrill’s two-spot octopus is generally grey and has characteristic blue spots, which are called ocelli and are found at the base of the second and third pair of arms (Castellanos, 2018). Their distribution in the world’s oceans ranges from the poles to the tropics (Boyle and Boletzky, 1996) and in Mexico we can find them along the Mexican Pacific and Gulf of California (SEPESCA, 2015).

There are different methods in Mexico to catch octopus, for instance, the extraction by means of scuba and the use of hooks and traps. However, in the San Quintín Lagoon Complex there are still techniques being used that are forbidden by the NOM-064-SAG/PESC/SEMARNAT-2013, a law that regulate the art and techniques for octopus fishing and catching in Mexico. One of these techniques is the use of toxic compounds like bleach, this consists on pouring it into possible hideouts of the organism, forcing it to get out, catching the octopus easier. This is an easy and low-cost technique that has been popular among fishermen.

Nonetheless, using chlorinated substances represents a problem for the environment, since it harms both the octopus and the organisms around it (Gonzalez-Melendez, 2012). This happens due to the fact that chlorinated compounds release ions that bind to carbon atoms, creating organochlorine compounds, which when dissolved in water can disperse and affect distant places from their place of origin (Padilla, 2005) resulting in harm for humans and other living beings. Organochlorinated compounds are carcinogenic, affecting the immune, reproductive and nervous systems. These compounds are accumulated in the fat tissue which increases its concentration as they ascend in the food chain (Santamarta, 2000).

Due to the importance of octopus fishing in the region, the use of these illegal practices for its extraction can lead to ecological as well as health negative effects, for the octopus and the living beings that coexist, integrating the human being, consumer and user of this resource and of the sea.