The ENSO signature in sea-surface temperature in the Gulf of California

We analyzed 21 years of sea-surface temperature satellite images to explore the spatial signature of the El Niño-Southern Oscillation signal in the Gulf of California. We used empirical orthogonal function analysis to extract the principal mode of the nonseasonal sea-surface temperature variability and compared it to the spatial signature of the Southern Oscillation Index. The first mode accounted for 80% of nonseasonal variability and its amplitude time series was significantly correlated to the Southern Oscillation Index (r = −0.58,P \u3c 0.01). The amplitude of this mode and its statistical relation to the El Niño is stronger during winter, which suggests that forcing of sea-surface temperature variability occurs through the disruption of the wind-driven upwelling corridor along the eastern coast due to El Niño-related atmospheric teleconnections. We also examined weekly time series of coastal sea-surface temperature coastal anomalies along the coast of North America, including the interior of the Gulf of California, during the strong 1997–98 El Niño. We found a poleward propagating signal that reached the mouth of the Gulf of California at the end of spring and continued its poleward propagation along the west coast of the peninsula slightly delayed; it also resulted in warming inside the Gulf of California. This observation may provide an explanation for the variable extension of the El Niño signature along the Pacific coast of North America

Perspectives for implementing fisheries certification in developing countries

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

Composición, estructura y diversidad del mesozooplancton en Las Guásimas, Sonora, un sitio Ramsar en el Golfo de California, durante 2010

 The mesozooplankton community of Las Guásimas, a coastal lagoon at the coast of Sonora, Mexico, was investigated to determine, for the first time, their composition, structure and diversity monthly, given the high ecological and fisheries importance of this ecosystem and its designation as a RAMSAR site. Sampling was conducted at two representative sites from January to December 2010 with a conical net of 300 microns, recording environmental variables (temperature, salinity, dissolved oxygen). Settled volume, density and identity of mesozooplankton samples were determined. Seventy eight taxa were identified in samples, which were dominated by Acartia tonsa (66.9%) and Penilia avirostris (9.9%). Other important groups were chaetognaths, fish eggs, gastropods, and larvaceans. The density of organisms within the lagoon was higher than outside, where diversity was higher. The results suggest that the abundance, composition and diversity of the zooplankton community of Las Guásimas are influenced by environmental variables, mainly sea surface temperature, and biological aspects, such as predation and reproductive pulses. However, for a better understanding of the complex interactions observed it is necessary to continue with a regular monitoring of the ecosystem to generate long series of data to assess patterns of long-term change, given its uniqueness and ecological and economic importance in the Gulf of CaliforniaSe analizó el mesozooplancton de Las Guásimas, una laguna costera semiárida de la costa de Sonora, México, con el objetivo de determinar por primera vez su composición, estructura y diversidad mensual, dada la gran importancia eco­lógica y pesquera de este ecosistema y su designación como sitio RAMSAR. El muestreo se llevó a cabo en dos sitios representativos desde enero a diciembre de 2010 con una red cónica de 300 micras e incluyó el registro de variables am­bientales (temperatura, salinidad, oxígeno disuelto). Se determinó el volumen, la densidad y la identidad del zooplancton colectado. Se identificaron setenta y ocho taxa en las muestras, donde predominaron Acartia tonsa (Dana 1849) (66.9%) y Penilia avirostris (9.9%). Otros grupos importantes fueron quetognatos, huevos de peces, gasterópodos y larváceos. En promedio, la densidad de los organismos dentro de la laguna fue mayor que en el exterior, donde la diversidad fue mayor. Los resultados sugieren que la abundancia, composición y diversidad de la comunidad zooplanctónica de las Guásimas, son influenciadas por variables ambientales, principalmente la temperatura superficial del mar, y factores biológicos, tales como depredación y probables pulsos reproductivos. Sin embargo, para una mejor comprensión de las interacciones complejas observadas, es necesario continuar con el muestreo regular de Las Guásimas, con la finalidad de generar series largas de datos para evaluar patrones de cambio de largo plazo, dada su singularidad, relevancia ecológica y económica en la región del Golfo de Californi

A review of recent and future marine extinctions

Between 20 and 24 marine extinctions, ranging from algal to mammal species, have occurred over the past 500 years. These relatively low numbers question whether the sixth mass extinction that is underway on land is also occurring in the ocean. There is, however, increasing evidence of worldwide losses of marine populations that may foretell a wave of oncoming marine extinctions. A review of current methods being used to determine the loss of biodiversity from the world’s oceans reveals the need to develop and apply new assessment methodologies that incorporate standardized metrics that allow comparisons to be made among different regions and taxonomic groups, and between current extinctions and past mass extinction events. Such efforts will contribute to a better understanding of extinction risk facing marine flora and fauna, as well as the ways in which it can be mitigated

An analysis of the impacts of climatic variability and hydrology on the coastal fisheries, Engraulis encrasicolus and Sepia officinalis, of Portugal

The notion that climate change may impact coastal fish production suggests a need to understand how climatic variables may influence fish catches at different time scales. Evidence suggests that the effect of climatic variability and fishing effort on landed catches (as proxy of fish abundance) may vary at the regional scale. This study aims to assess the sensibility of two commercial species with a short life cycle (Engraulis encrasicolus and Sepia officinalis) to climatic and fisheries effects across different regions of the coast of Portugal: northwestern, southwestern and southern Portugal. The effect of environmental explanatory variables, i.e. NAO index, sea surface temperature (SST), upwelling (UPW) index, river discharge, wind magnitude (WmaG), wind direction (Wdir), and fishing variables (fishing effort) on catch rates time series were studied between 1989 and 2009. The sensibility of the species studied to climatic variability differed among regions and were explained by different climatic variables. River discharge had a significant effect on catch rates of the two species, region independently. However, wind driven phenomenon and UPW were the variables that better explained the observed fishing trends across the three regions. Changes in catch rate trends among the studied regions, at a given time, were mostly associated with the reproduction periods of the species. Therefore, regional analyses will significantly contribute to a better understanding of the relationship between climate change and coastal fisheries, aiming to improve integrated coastal zone management

Shifts between gelatinous and crustacean plankton in a coastal upwellin region

proyectos RADIALES (IEO) y EURO-BASIN (Ref. 264933, 7FP)Variability in the dominance of copepods vs. gelatinous plankton was analysed using monthly time-series covering the last 55 years and related to changes in climatic, oceanographic, and fishery conditions in the upwelling region of Galicia (NW Spain). Seasonality was generally the main component of variability in all groups, both along the coast and in the nearby ocean, but no common long-term trend was found. Coastal copepods increased since the early 1990s, and gelatinous plankton increased in the ocean during the 1980s. Different trends were found for gelatinous plankton in two coastal sites, characterized by increases in either medusae or tunicates. In all series, multiyear periods of relative dominance of gelatinous vs. copepod plankton were evident. In general, copepod periods were observed in positive phases of the main modes of regional climatic variability. Conversely, gelatinous periods occurred during negative climatic phases. However, the low correlations between gelatinous plankton and climatic, oceanographic, or fishery variables suggest that local factors play a major role in their proliferations.7FP, IEOPreprin

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

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