Modelling a Small-Scale Sea Cucumber Fishery in Yucatan

The status of many sea cucumber fisheries in the world is overexploited. Some of the reasons are: an increase in demand from China, the distance of these fisheries to China, and the high rate of fisheries development. Most sea cucumber fisheries are small-scale with a simple management system. To overcome overexploitation, it is important to know the fisheries management systems. The research questions of this study are: What are the biological and economic factors that accelerate the development of these fisheries? What factors threaten the sustainability of these stocks? And what possible strategies could be implemented? With biological information of the species, fishermen behavior, and the economics, we developed a spatial dynamic bioeconomic model. The model explained the interactions between fishing effort allocation, quasi-profits and population depletion. Our results showed that the main factors that could lead the fishery to the collapse are: a) the spatial pattern, b) excess fishing capacity, c) high quasi-profits in the short term, d) density dependent catchability, and e) heavy density dependence of reproduction. Given the high prices, production, and low opportunity cost of fishers in tropical countries, they often prefer to maximize their short-term gains, regardless of long-term losses due to collapse. Ensuring sustainability requires community agreements and regulations like: minimum legal size, quotas, catch limit per trip, season closed to fishing and rotation of participants

Modelación espacial de la estructura y distribución de la población de caracol rosado (Aliger gigas) en Pedro Bank, Jamaica

The estimation of reliable indices of abundance for sedentary stocks requires the incorporation of the underlying spatial population structure, including issues arising from the sampling design and zero inflation. We applied seven spatial interpolation techniques [ordinary kriging (OK), kriging with external drift (KED), a negative binomial generalized additive model (NBGAM), NBGAM plus OK (NBGAM+OK), a general additive mixed model (GAMM), GAMM plus OK (GAMM+OK) and a zero-inflated negative binomial model (ZINB) ] to three survey datasets to estimate biomass for the gastropod Aliger gigas on the Pedro Bank Jamaica. The models were evaluated using 10-fold cross-validation diagnostics criteria for choosing the best model. We also compared the best model estimations against two common design methods to assess the consequences of ignoring the spatial structure of the species distribution. GAMM and ZINB were overall the best models but were strongly affected by the sampling design, sample size, the coefficient of variation of the sample and the quality of the available covariates used to model the distribution (geographic location, depth and habitat). More reliable abundance indices can help to improve stock assessments and the development of spatial management using an ecosystem approach.Las estimaciones de índices de abundancia relativa para evaluar poblaciones de especies sedentarias requieren tener en cuenta su estructura espacial, el diseño del muestreo y el alto número de ceros registrados a la hora del muestreo. Para obtener un índice confiable de abundancia para el gasterópodo Aliger gigas en Pedro Bank, Jamaica, se aplicaron siete técnicas de interpolación espacial a tres conjuntos de datos: kriging ordinario (OK), kriging con desviación externa (KED), modelo aditivo generalizado binomial negativo (NBGAM), NBGAM más OK (NBGAM+OK), modelo mixto aditivo general (GAMM), GAMM más OK (GAMM+OK) y modelo binomial negativo con ceros inflados (ZINB). La selección de los mejores modelos espaciales se basó en el criterio de validación cruzada con 10 iteraciones; asimismo, se aplicaron métodos de evaluación comúnmente usados, para destacar la importancia de tener en cuenta la estructura espacial de la distribución de la especie. Los mejores modelos fueron GAMM y ZINB, los cuales fueron fuertemente influenciados por el diseño de muestreo, el tamaño de muestra, el coeficiente de variación y la calidad de las covariables empleadas en la modelación (ubicación geográfica, profundidad y hábitat). Los índices de abundancia más confiables pueden contribuir a mejorar las evaluaciones y desarrollar el manejo espacial con enfoque de ecosistema

Co-Management of a Recreational Fishery with a Social-Ecological Approach

Most regulations for recreational fishing in Mexico focus primarily on offshore boat fishing. However, regulations for inshore recreational fishing in Mexico are insufficient. Every year hundreds of European and American fishermen visit Punta Allen, Mexico to practice fly-fishing. Punta Allen is a coastal village located in the Sian Ka'an Biosphere Reserve, Quintana Roo.  For many years, locals have been organized for a sustainable management of lobster fishing. This experience let them to organize and develop internal regulations to manage the newly created fly-fishing activity. The objective of this study is to assess the economic spill from fly-fishing in the community. With data from semi-structured questionnaires to fishing guides and records of cooperatives, the contribution of this activity to the sustainability is explained by describing the internal organization. We observed that in order to increase profits, villagers organized themselves into cooperatives and established alliances with private firms, some of these from the United States. These companies make contact with anglers abroad and offer them all-inclusive packages per day and/or week, including ground transportation, accommodation, meals, and hire local guides with their own boats to take fishermen to fly fishing sites. Local guides have organized five cooperatives to avoid unfair competition by establishing agreements, maximum number of boats, and schedules. Despite few private external firms acquired licenses to provide fly-fishing guiding services, most licenses belong to local cooperatives, which has empowered them in the alliances to co-manage the activity

Biomasa potencial y distribución de pulpo en el este del banco de Campeche (Yucatán, México)

The octopus fishery on the Campeche Bank (Yucatán, Mexico) is considered the third largest in the world. In Yucatán, two fleets target this resource: an artisanal fleet and a semi-industrial fleet. The artisanal fleet only catches Octopus maya, while the semi-industrial fleet catches two species, O. Maya and O. “vulgaris” Type II, because it operates at deeper waters ( > 30 m). Since there is no information on the abundance of O. “vulgaris” Type II, management is based only on O. Maya. In order to generate information about the abundance of this species, four fishing research cruises were carried out in the northeastern area of the continental shelf off the Yucatán Peninsula. Four methods (a stratified random method, a swept area, geostatistics and a weighted swept area) were applied and compared to determine the instantaneous abundance and biomass of both species in the study area. The lowest potential biomass was calculated with the geostatistical method, with values between 18.5% and 36.7% lower than the other three methods. O. “vulgaris” Type II showed the lowest biomass (37.8±3.36 t) during May and July and the highest (189.56±11.6 t) in December. Our findings revealed that the total abun­dance of both species was similar in the study area, with a geographic overlap whose amplitude changed throughout the year according to the geographic position: O. Maya dominated at approximately 88°W, while O. “vulgaris” Type II dominated towards the southeast at 87°W.La pesquería de pulpo en el banco de Campeche (Yucatán, México) se considera la tercera productora mundial de pulpo. En Yucatán, dos flotas capturan este recurso: una flota artesanal y una semi-industrial. La flota artesanal solo captura Octopus maya, mientras que la flota semi-industrial captura dos especies: O. Maya y O. “vulgaris” Tipo II. Esto se debe a que la flota semi-industrial opera en aguas más profundas ( > 30 m). Dado que no existe información sobre la abundancia de O. “vulgaris” Tipo II, el manejo se basa únicamente en la evaluación de O. Maya. Con objeto de generar información sobre la abundancia de esta especie, se realizaron cuatro campañas de prospección pesquera en la zona noreste de la plataforma con­tinental de la Península de Yucatán. Se aplicaron cuatro métodos (método aleatorio estratificado, área barrida, geoestadística y área barrida ponderada) y sus resultados se compararon para determinar la abundancia y biomasa instantáneas de ambas especies en el área de estudio. La biomasa potencial más baja se obtuvo con el método geoestadístico, con valores de 18.5 a 36.7% más bajos que con los otros tres métodos. O. “vulgaris” Tipo II mostró una biomasa más baja (37.8±3.36 t) durante mayo y junio, mientras que la más alta (189.56±11.6 t) fue en diciembre. Nuestros hallazgos revelaron que la abundancia total para las dos especies fue similar; además ambas especies presentaron una superposición geográfica, cuya amplitud cambió con el período del año y la posición geográfica: O. maya fue dominante en la longitud de los 88°W, mientras que O. “vulgaris Tipo II dominó hacia el sudeste de la plataforma de Yucatán (aproximadamente 87°W)

Genetic and environmental factors related to the development of myopic maculopathy in Spanish patients

High myopia and the subsequent degenerative changes of the retina, choroid, and sclera, known as myopic maculopathy (MM), are a serious visual problem in many Asian countries, and are beginning to be so in the south of Europe, especially in the Mediterranean. It is therefore necessary to carry out genetic and environmental studies to determine the possible causes of this disease. This study aims to verify if the genetic factors that have been most related to Asian populations are also associated in two Spanish cohorts. Eight SNPs from six genes (PAX6,SCO2,CCDC102B,BLID,chromosome 15q14, andCOL8A1) along with demographic, ophthalmic and environmental factors were analysed in two cohorts from a total of 365 highly myopic subjects and 177 control subjects. The genetic analysis showed thatCOL8A1SNP rs13095226 was associated with the development of choroidal neovascularization (CNV) and also seems to play an important role in the increase of axial length. The SNP rs634990 ofchromosome 15q14also showed a significant association with MM, although this was lost after the Bonferroni correction. Additional demographic and environmental factors, namely age, sex, smoking status, and pregnancy history, were also found to be associated with MM and CNV in this population

Long-term follow-up of certolizumab pegol in uveitis due to immune-mediated inflammatory diseases : multicentre study of 80 patients

Objectives To evaluate effectiveness and safety of certolizumab pegol (CZP) in uveitis due to immune-mediated inflammatory diseases (IMID). Methods Multicentre study of CZP-treated patients with IMID uveitis refractory to conventional immunosuppressant. Effectiveness was assessed through the following ocular parameters: best-corrected visual acuity, anterior chamber cells, vitritis, macular thickness and retinal vasculitis. These variables were compared between the baseline, and first week, first, third, sixth months, first and second year. Results We studied 80 (33 men/47 women) patients (111 affected eyes) with a mean age of 41.6±11.7 years. The IMID included were: spondyloarthritis (n=43), Behçet's disease (n=10), psoriatic arthritis (n=8), Crohn's disease (n=4), sarcoidosis (n=2), juvenile idiopathic arthritis (n=1), reactive arthritis (n=1), rheumatoid arthritis (n=1), relapsing polychondritis (n=1), Conclusions CZP seems to be effective and safe in uveitis related to different IMID, even in patients refractory to previous biological drugs