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    • "e huevos ocurre en abril, aunque INAPESCA menciona que en algunos años puede ocurrir en marzo o febrero; sin embargo, como las capturas de sardina están limitadas a 20 km de la costa, estas estimaciones podrían estar fuertemente sesgadas ya que en primavera, las offshore to spawn during spring to avoid the recently upwelled, colder water nearshore.Baumgartner et al. (2008)showed the distribution and relative concentration of eggs in CUFES samples occurring outside the upwelling fronts in spring, parallel to the coast between 50 and 200 km offshore. The information of the spawning habitat inferred by the presence of eggs indicated a high probability of finding reproductive adults of sardines that were not "
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    ABSTRACT: Due to their sensitivity to climate forcing that may alter their abundance and distribution, small pelagic fish are important ecological indicators of the state of the California Current System. They are schooling, planktivorous fish that provide forage for higher trophic levels. We describe the life cycle histories and patterns of distribution of sardine, anchovy, and mackerel species occupying the waters along the west coast of the Baja California Peninsula (Mexico). The links between the physical and biological forcing and the structure and condition of their habitats, their patterns of movement, productivity, and stock structure (where information is available) are described in relation to the fisheries. We have used the catches as a proxy for the history of the different stocks, while recognizing that fisheries-derived information is biased by the operational scale and only covers areas where fish are available. We have relied mainly on studies of sardines to evaluate the validity of the principal paradigms in fisheries oceanography. We describe how the environment can structure a population by relating an example given by the spatiotemporal variability of the northern and southern stocks of Pacific sardine (Sardinops sagax) and Pacific mackerel (Scomber japonicus) from 2000 to 2014. During this period, the northern stocks showed a marked tendency to contract southwards, as far south as Magdalena Bay, in response to the regional cooling that began in the previous decade. It appears that the combined effects of fishing and climate change may sufficiently alter habitat characteristics so that both the distribution and productivity of a population are shifted. © 2015 Universidad Autonoma de Baja California. All rights reserved.
    Full-text · Article · Dec 2015
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    • "2 – 50°N . His - torically , alongshore coherence of zooplankton biomass and com - position variability extended further south to include much of Baja California ( 24 – 32°N ) , but during at least the past decade zoo - plankton populations off Baja have varied inversely with more northerly parts of the California Current ( Mackas et al . , 2006 ; Baumgartner et al . , 2008 ) . Lavaniegos and Ambriz - Arreola ( 2012 ) provide a more detailed analysis of recent interannual variability of euphausiids off Baja California , and confirm that variations have been out - of - phase with more northerly locations . Highest biomass occurred during the 1998 El Niño event , and high abundance of ' ' northern ' ' specie"
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    ABSTRACT: The work highlights the first Global Comparison of Zooplankton Time Series. Variation of the peak in abundance is affected by annual temperature anomalies. Results show no global-scale synchrony in zooplankton time-series. There are spatial autocorrelations over substantial distances (1000-3000 km). There remains considerable uncertainty about the relative causes of shifts in distributions.
    Full-text · Article · May 2012 · Progress In Oceanography
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    ABSTRACT: The variability of the mixed layer depth (MLD) is examined over a decade (1997-2007) for the tropical boundary of the California Current (24-32°N), using conductivity-temperature-depth observations collected by quarterly survey cruises. Results indicate that salinity gradients control MLD rather than temperature gradients. The mean state of the upper ocean indicates that contours of constant MLD are parallel to the coast, with mixed layer thickness decreasing toward the coastal zone. The deepest (˜70 m) thickness is reached in January and the shallowest (˜15 m) occurs in July. The warmer conditions (summer) are reproduced for a simple thermal energy equation. The rest of the seasons are reproduced for a one-dimensional momentum balance for the upper ocean, which includes Ekman dynamics and stratification. This comparison indicates that the variability of MLD is mainly due to wind-driven phenomena except during the heating period. In particular, seasonal and interannual variability of the MLD are correlated with offshore Ekman transport. An abrupt MLD change occurs between January 1998 and January 2000 associated with the strong El Niño-La Niña cycle shift that occurred in this period.
    No preview · Article · May 2010 · Journal of Geophysical Research Atmospheres
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