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The loggerhead turtle (Caretta caretta) is a circumglobal species and is listed as vulnerable globally. The North Pacific population nests in Japan and migrates to the Central North Pacific and Pacific coast of North America to feed. In the Mexican Pacific, records of loggerhead presence are largely restricted to the Gulf of Ulloa along the Baja California Peninsula, where very high fisheries by-catch mortality has been reported. Records of loggerhead turtles within the Sea of Cortez also known as the Gulf of California (GC) exist; however, their ecology in this region is poorly understood. We used satellite tracking and an environmental variable analysis (chlorophyll-a(Chl-a) and sea surface temperature (SST)) to determine movements and habitat use of five juvenile loggerhead turtles ranging in straight carapace length from 62.7–68.3 cm (mean: 66.7 ± 2.3 cm). Satellite tracking durations ranged from 73–293 days (mean: 149 ± 62.5 days), transmissions per turtle from 14–1006 (mean: 462 ± 379.5 transmissions) and total travel distance from 1237–5222 km (mean: 3118 ± 1490.7 km). We used travel rate analyses to identify five foraging areas in the GC, which occurred mainly in waters from 10–80 m deep, with mean Chl-aconcentrations ranging from 0.28–13.14 mg m−3and SST ranging from 27.8–34.4°C. This is the first study to describe loggerhead movements in the Gulf of California and our data suggest that loggerhead foraging movements are performed in areas with eutrophic levels of Chl-a.

The Gulf of California Large Marine Ecosystem (LME) is one of the most productive and biologically rich marine ecosystems in the world with a high rate of endemic species. The combination of high biological productivity and biological richness characterizing the region is the result of its unique geology and geography, shaping strong currents and tides that generate the upwelling of cool, nutrient-rich waters. These waters support an extremely high abundance of plankton that in turn is the basis of a complex food web sustaining a diversity of fish, birds, and marine mammals. As Mexico's most important fishery region, the Gulf of California provides seafood to locals and for export to other countries. In addition, manifold coastal lagoons, coastal marine sea-beds, mangrove forests, and 922 islands are important reproductive, nesting and nursing sites for hundreds of resident and migratory bird species. However, even when several oceanographic processes that confer a high productivity to the Gulf of California LME have been documented, there is very little field work to monitor these phenomena, such as coastal upwelling in the southern region, as well as the spatial and temporal variability in nutrient concentrations, the effect of exchange with coastal systems and the role of the Gulf of California as a sink or exporter of carbon dioxide (CO₂), for example, in winter the region of the Grandes Islas , there are a source of CO 2 to the atmosphere (pCO 2 >580 µatm). On this, the records show that in the last 250 years the concentrations of atmospheric CO₂ in the world have increased and it has been reported that the ocean daily fixed 2.2 metric tons of CO₂, this content has changed from 280 µatm before the industrial revolution to 407 µatm in recent times. In the Gulf of California, studies conducted on carbon dioxide (air-ocean flow, dissolved inorganic carbon, total alkalinity) are scarce, and suggest a net flow CO 2 from coastal waters into the atmosphere mainly in the region of the Grandes Islas , caused by the intense vertical mixing. In the absence of time-series data on the processes occurring in the southern part of the Gulf, it is necessary to start continuous records of temperature, salinity, dissolved oxygen, pH vertical structure and the measurements of dissolved inorganic carbon, total alkalinity and nutrients to improve understanding of the biogeochemical structure of the water column and possible exchanges with the coast.

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El dengue es una enfermedad viral en humanos transmitida por el mosquito A. aegypti (L), principal vector en América. En el 2006 en Sinaloa México se presentaron 477 casos de dengue hemorrágico y 1 510 de dengue clásico, el estado presentó el mayor número de casos de dengue hemorrágico del país, debido a esto se realizó un estudio sobre la abundancia y distribución del mosquito de abril 2008 a agosto 2009 en Guasave Sinaloa, México. La Ciudad se dividió en seis sectores, en la cual se consideraron 16 colonias con el mayor número de casas por sector; se colocaron 96 trampas para monitorear la densidad de población del insecto y el número de hembras por trampa, esto datos sirvieron para calcular los índices de densidad de adultos (IDA) e índice de trampas positivas (ITP) por sector, los cuales junto con los casos de dengue permitieron elaboraron mapas de dispersión de la enfermedad. En julio y agosto se registró la abundancia más alta de hembras (137 y 139). En agosto y septiembre los sectores dos, cuatro y seis presentaron valores de IDA de 2.44, 3.35 y 2.29, por lo que fueron de un alto riesgo epidemiológico, mientras que en estos mismos sectores se encontraron los valores más altos de ITP (56.25, 58.82 y 61.54). Los valores de mayor asociación de las correlaciones entre la abundancia poblacional de hembras se obtuvo con la precipitación (r=0.80) y con la temperatura promedio (r=0.76), a cero meses de retraso. La correlación entre el DC/DH con la precipitación fue más alta (r=0.98) que con la temperatura mínima (r=0.79); ambas con dos meses de retraso. En este estudio se demostró que los mapas mensuales de dispersión epidemiológica sirven como una medida del riesgo de la enfermedad en Guasave, Sinaloa.Abundance and distribution of Aedes aegypti (Diptera: Culicidae), and dengue dispersion in Guasave Sinaloa, México. Dengue is an important disease that affects humans, and is transmitted by A. aegypti. During 2006, a total of 477 cases of hemorrhagic dengue, and 1 510 of classic dengue were recorded in Sinaloa. Due to this high impact, a study on insect abundance and distribution, as well as their relationship with dengue dispersion, was carried out from April 2008 to March 2009 in Guasave, Sinaloa. The study included a total of six sectors in the city, considering 16 colonies; besides, 96 traps were distributed in these sectors to monitor the vector population density and female number per trap. The adult density index (ADI) and traps positive index (TPI) were calculated, and data were used to obtain the monthly dengue dispersion maps. The highest abundance of female (137 and 139) was found in July and August. In August and September the sectors 2, 4 and 6 showed the highest ADI values 2.44, 3.35 and 2.290, while TPI values were 56.25, 58.82 and 61.54, with the highest epidemiology dengue dispersion. The Pearson correlation (p

The seasonal variability of dissolved inorganic nutrients (phosphates, PO–3 4; nitrates, NO– 3; nitrites, NO– 2) and chlorophyll a was studied during fiv...

[1] Using satellite sea surface height (SSH) and chlorophyll (CHL), the year 2000 is analyzed to characterize the effects of mesoscale circulation patterns on phytoplankton spatial variability in the California Current (CC) off Baja California. Satellite data are combined with and compared to in situ field measurements (chlorophyll-a and hydrographic variables) along vertical alongshore sections located ∼130 km offshore between ∼24.5° −33°N. Monthly average maps of SSH and surface geostrophic velocities depict the characteristics of mesoscale meanders and eddies, which correspond well with the subsurface hydrographic and velocity fields. Satellite-derived pigment (CHL) represent in situ fields in the upper 0–20 m (overall r = 0.53; p < 0.05), but their representation of peak values in Deep Chlorophyll Maxima (DCM) at ∼50 m depth are inaccurate. DCM are traced in all three seasons (January–July), descending from near the surface (north of 31°N) to 50 m over a large extent of the transect to the south, approximately following the 24.7–25.1 isopycnals as they and the isotherms deepen to the south. In January, phytoplankton chlorophyll concentrations in the DCM are relatively uniform, originating during upwelling events that occur farther north, then following the equatorward flow of the CC. During April and July, the discrete maxima in the DCM occur at the centers of cyclonic meanders and the chlorophyll concentrations inside these maxima are enhanced as a result of local coastal upwelling off Baja California. Phytoplankton blooms created by coastal upwelling spread offshore and subduct along the 24.7–25.1 isopycnals, creating the DCM along the inner part of the meandering jet.

El Golfo de California es caracterizado como un mar semicerrado y una cuenca de evaporación. Se ha divido en varias zonas físicas y biogeográficas, características dadas por la dinámica de cada zona. El objetivo de este trabajo fue el de conocer la variabilidad interanual de la clorofila de Septiembre de 1997 a Diciembre de 2002 bajo condiciones El Niño y La Niña. Se obtuvieron del sensor SeaWiFS los compuestos semanales de clorofila con resolución de 9 km por píxel, para el periodo de estudio. Los resultados más sobresalientes de la distribución promedio de clorofila sugiere que el Golfo de California puede dividirse en tres zonas: oligotrófica (boca del golfo), mesotrófica (parte central) y eutrófica (región costera y parte norte del golfo, incluida la región de las Grandes Islas). La estacionalidad de la clorofila indica la predominancia de la señal anual. Es evidente la variabilidad interanual producida por los eventos El Niño 1997-1998 y por La Niña 1998-2001. El efecto de El Niño 1997-1998 es fuerte sobre la distribución de clorofila, el cambio hacia condiciones frías de La Niña durante 1998-1999 se refleja en anomalías negativas de biomasa fitoplanctónica, pero en positivas en los años 2000 y 2001