It was determined the population genetic structure of the red octopus Octopus maya in the states of Campeche and Yucatan in Yucatan Peninsula, Mexico, through the expression of isozymes in polyacrylamide gels. Mantle samples from 25 octopuses, captured in nine sites of the Yucatan Peninsula, were used to characterize the genotypic expression revealed by the expression of 26 loci in thirty enzyme systems. Program TFPGA version 1.3 (Tools for Population Genetic Analyses), was used to process data of allozyme gene frequencies of the studied populations. The parameters determined were: descriptive statistics, F statistics, genetic distances, Hardy - Weinberg, UPGMA and the number of migrants as an indicator of gene flow. The average number of alleles per locus, percentage of polymorphic loci, average and direct and direct heterozygosity were: 1.08 ± 0.05 to 1.15 ± 0.04. P95 26.9231% to 34.6154, Have 0.1142 to 0.1390 and Hdir = 0.0354 to 0.0938 respectively. Heterozygosity values in a range of 0.3506 to 0.4793 and G6PDH for ARGK with an average heterozygosity value of 0.1824, Fisher average value of 0.5313 and 0.0140 Fst indicates a heterozygous deficiency but it is within the ranges reported for marine invertebrate species. The number of migrants derived from the Slatkin equation is 1824 per generation, globally indicates some degree of variability between sites and is consistent with the low values of Nei genetic distance found, particularly the node showing the separation of the population of Lagartos River and Dzilam Bravo from the other locations with an obtained value of 0.0004. From the results of this study, it is concluded that locations of Octopus maya have a certain level of interpopulation genetic variability that does not reflect its fragility.

The aim of this paper is to analyze the contributions of some tools developed with integrative approaches for managing water quality, considering the particular case of Cienfuegos Bay, Cuba. One of the contributions was related to the improvement of a hydrologic monitoring program of this bay with the assimilation of Environmental Totality and Integrated Watershed and Coastal Area Management (IWCAM) approaches. The development of an index for assessing water quality (WQI) of estuarine systems associated with a methodology for implementing a conceptual model on the eutrophication management from systemic and causal approaches, were another developed tools. In addition, a strategic program as a guide for the integrated management of this bay was included considering the participatory and systemic approaches. The assimilation of these integrative approaches for developing scientific tools allowed improving the environmental management at a contextual level and could be generalized in similar aquatic systems.

Se reportan varios brotes de intoxicación por ciguatera a partir del consumo de barracuda (Sphyraena barracuda) en los meses de julio y agosto de 2021, para la costa norte de la provincia de La Habana y Artemisa. Se discute acerca de la presencia de biotoxinas de ciguatera en esta especie y en las zonas donde habitan como posible riesgo de incidencia a la intoxicación. Se mencionan otros reportes de ciguatera por barracuda y la presencia de las biotoxinas presentes. También se discute de ecosistemas donde se pesca y se consume la barracuda sin ningún riesgo o reportes durante muchos años o incidencia relevante, lo cual sugiere debe atenderse a un manejo diferenciado de las especies en cada región según las características del ecosistema en cuanto a ecología con énfasis del fitoplancton. Se dan recomendaciones que deben ser consideradas para el manejo de este fenómeno en la región.