Acoustic observations of the vertical distribution and latitudinal range of small pelagic fish schools in the Midriff Islands Region, Gulf of California, Mexico

• DOI: 10.3856/vol46-issue5-fulltext-12
• Publication Date: 2018-11-26T15:09:09Z
• Authors: Uriel Rubio; Hector Villalobos; Manuel Nevarez
• Keywords: Diel vertical migration

Within the Gulf of California, Midriff Islands Region (MIR) is characterized by mixing conditions water masses that lead to high primary productivity, which fosters presence sardines, anchovies, and their predators.Using acoustic tools, we analyzed characteristics schools detected in three surveys carried out late spring 2012 2013 early summer 2014.We sought relate changes geographical distribution with Sea Surface Temperature (SST) Net Primary Productivity (NPP).The largest number was observed 2012, coinciding highest most extensive NPP, while following years were associated lower NPP coupled a detections.During study period, Ballenas-Salsipuedes Channel its area influence showed lowest SST higher even toward as compared rest MIR, favoring fish supporting importance this site feeding center for these species.As vertical distribution, it found during day reach greater depths, night are concentrated surface waters.However, no differences size, density, or other either between periods years.Finally, proportion (61%), departs from typical nocturnal dispersal behavior described similar species areas.