45 research outputs found

    Perspectives for implementing fisheries certification in developing countries

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    This paper discusses the future of the Marine Stewardship Council (MSC), a market-based certification program, in developing countries and exposes the challenges and opportunities for fish producers. The MSC needs to attract the interest of more fishing enterprises from these regions to increase its global presence. Because most fisheries in developing countries cannot meet the MSC standards, or afford the certification process costs, it is suggested that there is a need for developing different levels within the MSC system and additional third-party assessing organizations. MSC certification may mean adoption of improvements in fisheries management and approving fishing regimes in developing countries. However, post-certification benefits may decrease as more fisheries become certified

    Genetic Signature of Rapid IHHNV (Infectious Hypodermal and Hematopoietic Necrosis Virus) Expansion in Wild Penaeus Shrimp Populations

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    Infectious hypodermal and hematopoietic necrosis virus (IHHNV) is a widely distributed single-stranded DNA parvovirus that has been responsible for major losses in wild and farmed penaeid shrimp populations on the northwestern Pacific coast of Mexico since the early 1990's. IHHNV has been considered a slow-evolving, stable virus because shrimp populations in this region have recovered to pre-epizootic levels, and limited nucleotide variation has been found in a small number of IHHNV isolates studied from this region. To gain insight into IHHNV evolutionary and population dynamics, we analyzed IHHNV capsid protein gene sequences from 89 Penaeus shrimp, along with 14 previously published sequences. Using Bayesian coalescent approaches, we calculated a mean rate of nucleotide substitution for IHHNV that was unexpectedly high (1.39×10−4 substitutions/site/year) and comparable to that reported for RNA viruses. We found more genetic diversity than previously reported for IHHNV isolates and highly significant subdivision among the viral populations in Mexican waters. Past changes in effective number of infections that we infer from Bayesian skyline plots closely correspond to IHHNV epizootiological historical records. Given the high evolutionary rate and the observed regional isolation of IHHNV in shrimp populations in the Gulf of California, we suggest regular monitoring of wild and farmed shrimp and restriction of shrimp movement as preventative measures for future viral outbreaks

    Oceans and Coastal Ecosystems and Their Services

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    Ocean and coastal ecosystems support life on Earth and many aspects of human well-being. Covering two-thirds of the planet, the ocean hosts vast biodiversity and modulates the global climate system by regulating cycles of heat, water and elements, including carbon. Marine systems are central to many cultures, and they also provide food, minerals, energy and employment to people. Since previous assessments1 , new laboratory studies, field observations and process studies, a wider range of model simulations, Indigenous knowledge, and local knowledge have provided increasing evidence on the impacts of climate change on ocean and coastal systems, how human communities are experiencing these impacts, and the potential solutions for ecological and human adaptation.Peer reviewe

    Caso de estudio sobre el uso de bases de datos ambientales de baja resolución espacial, como una alternativa para inferir hábitat de desove.

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    En este trabajo se prueba la factibilidad de utilizar datos ambientales de baja resolución y fácil obtención para inferir hábitat de desove de la sardina monterrey del Golfo de California, en el dominio de la temperatura. Se compararon resultados publicados, basados en mediciones de temperatura asociadas al muestreo biológico, con cálculos a partir de datos extraídos de una base pública. Los resultados muestran que existen similitudes importantes entre ambas estimaciones, a pesar de las grandes diferencias entre las dos fuentes de datos. Este resultado es relevante para algunas iniciativas en curso, donde se pretende incorporar información ambiental, de fácil acceso y oportuna, a sistemas de información para la pesquería de sardina del Golfo de California

    Sea surface temperature anomalies, seasonal cycle and trend regimes in the Eastern Pacific coast

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    We used the extended reconstruction of sea surface temperature (ERSST) to analyze the variation of surface temperature and the seasonal cycle along the coast of the eastern Pacific (60° N–60° S, 61 pixels alongshore) from 1950 to 2010 (732 months). First, we analyzed the monthly anomalies and looked for a relationship of such anomalies with total solar irradiance (TSI) and then the Regime Shift Detector (RSD) was applied to detect possible temperature regimes in the series. Afterwards, we calculated a yearly temperature range per pixel (amplitude of seasonal cycle) and through the subtraction of a latitudinal theoretical curve of temperature based on solar irradiance, the residuals of the seasonal cycle were obtained. The results showed an almost complete spatial synchrony and dominance of negative anomalies from 1950 to mid-late 1970's, with a switch to near-zero and positive anomalies that lasted up to late 1990's when a new shift to negative values was detected. Such a shift lasted until the early 2000's when positive anomalies appeared again but there was a change to negative anomalies in the late 2000's. These results were supported by the RSD. The TSI variability shows a clear relationship with that of sea surface temperature anomalies and with the regime changes. This is probably due to a difference in the amount of energy received from the sun. Comparing the "cool regime" versus the "warm regime", the second one received 0.39% more energy (approximately 3 × 10<sup>8</sup> J m<sup>−2</sup>) from the sun. Seasonal cycles show larger ranges at northern latitudes (>40° N), northern tropical-temperate transition zone (20°–26° N) and in the tropical-equatorial band (0°–30° S). The smallest ranges occur at 0°–16° N and 50°–60° S. The residuals (seasonal minus the theoretical curve) indicated a clear modulation due to advection by ocean currents

    Recent trends in sea surface temperature off Mexico

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    Changes in global mean sea surface temperature may have potential negative implications for natural and socioeconomic systems; however, measurements to predict trends in different regions have been limited and sometimes contradictory. In this study, an assessment of sea surface temperature change signals in the seas off Mexico is presented and compared to other regions and the world ocean, and to selected basin scale climatic indices of the North Pacific, the Atlantic and the tropical Pacific variability. We identified eight regions with different exposure to climate variability: In the Pacific, the west coast of the Baja California peninsula with mostly no trend, the Gulf of California with a modest cooling trend during the last 20 to 25 years, the oceanic area with the most intense recent cooling trend, the southern part showing an intense warming trend, and a band of no trend setting the boundary between North-Pacific and tropical-Pacific variability patterns; in the Atlantic, the northeast Gulf of Mexico shows cooling, while the western Gulf of Mexico and the Caribbean have been warming for more than three decades. Potential interactions with fisheries and coastal sensitive ecosystems are discusse

    Multiscale characterization of the sea temperature in an area of abalone banks (Haliotis spp.) at Bahia Asuncion, Baja California Sur, Mexico

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    The Baja California abalone is one of the most important Mexican fisheries because of its high economic value. Despite strong management efforts, this fishery has faced dramatic fluctuations attributed mainly to overfishing and variability of the marine climate. In this report we analyze sea temperature variability off Bahía Asunción, Baja California Sur (Mexico), at temporal scales that may affect abalone biological processes, such as mortality, reproduction, recruitment, and individual growth rate. Since the analysis is based on different data sources, we conducted a series of correlation analyses to determine the coherence between them. We report the average daily cycle and its variations throughout the year and between years for the period 1997–2000, the seasonal cycle and interannual deviations for the period 1992–2000, the behavior of the decadal scale variability based on annual values for the period 1959–1997, and the long-term trends after analyzing the entire 20th century. Furthermore, we conducted a spectral density analysis to estimate the proportional contribution of each temporal scale to the entire variability signal. Results from the high-frequency variability (daily to interannual) suggest a relationship between temperature and the abalone reproductive cycles, a potential negative effect of the very strong ENSO events on the postlarvae, and a differential effect of temperature on juveniles of different species. Regarding the low-frequency variability (decadal to century), we show that recent years represent a much warmer period compared to previous decades, suggesting a different biological community structure between periods. The spectral density analysis indicates seasonal variability as the major contributor to the regional variability, followed by the interannual (related to ENSO). There is almost no information of the marine climate in this region, particularly in regard to fine and high-resolution observations. This contribution will provide new quantitative elements for studies dealing with the ecology of these coastal productive systems
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