Changes in marine faunal distributions and ENSO events in the California Current

Abstract

Interannual variability in the California Current System is analyzed through its effects on the temporal distribution of fauna, particularly southern-origin organisms moving north during warming events and south during cooling ones. In temperate waters north of 24°N latitude, northward movements of southern fauna occur at intervals of about 5 yr. This is different from El Niñ o events, whose frequency of occurrence is mostly centered in the 3-yr period but with considerable dispersion. Possible causes for northward displacement of fauna include relaxation of the California Current, intensification of the countercurrent, and the formation and persistence of mesoscale eddies among others. Strong events appear to be a consequence of the decadal variation peaks.

Anomalous pelagic nekton abundance, distribution, and apparent recruitment in the northern California Current in 2004 and 2005

“…It also has undergone substantial regime shifts, with subsequent effects rippling through all trophic levels [ Peterson and Schwing , 2003]. There is also substantial interannual variability, imposed, in part, by the northern manifestation of the El Nino‐Southern Oscillation (ENSO), which has a periodicity of roughly 3 years [ Lluch‐Belda et al , 2005].…”

“…Thus, the effects of unusual oceanographic events have been documented over time in terms of anomalous distribution or abundance of nekton [ Hubbs , 1948; Pearcy and Schoener , 1987; Pearcy , 2002]. Lluch‐Belda et al [2005] reviewed the literature describing the occurrence of allochthonous plankton and nekton of mostly southern origin in the CCR and concluded that their northward movement had a periodicity of about 5 years, thus not coherent with the ENSO cycle.…”

Interannual and interdecadal variability in juvenile coho salmon (Oncorhynchus kisutch) diets in relation to environmental changes in the northern California Current

“…Although known to occur every few years, many of these events are not of sufficient intensity to affect northern latitudes (Ware, 1995). However, two of the strongest El Niños on record occurred in 1982–83 and 1997–98 (Lluch‐Belda et al. , 2005), and both were followed by a short period of cool conditions (La Niñas).…”

The effect of Peruvian small‐scale fisheries on sunfishes (Molidae)

“…By‐catch events reported for Ancon and Chorrillos, in central Peru, occurred during the intense 2015–2016 El Niño southern oscillation (ENSO) event (National Oceanic and Atmospheric Administration [NOAA], ). Studies have reported changing distributions of several fishes including M. mola during ENSO events (Lluch‐Belda et al ., ; Sielfeld et al ., ). Thus, it is likely that the 2015–2016 ENSO would have affected sunfish distribution in Peruvian waters.…”