Bocaccio sounds in the Southern California Bight.

Abstract

Sound production by many fish species has been studied extensively, but little is known about sound production by rockfishes (genus Sebastes), and only a few species have been reported to be soniferous. Passive acoustic recordings were made during 2007 and 2008 at Hubbs‐SeaWorld Research Institute and Southwest Fisheries Science Center tanks containing Bocaccio (S. paucispinis). Sounds in tanks were recorded using preamplified hydrophones (HTI‐94‐SSQ) and were digitized at sample rates of 44,100 or 8000 Hz. Recordings were collected at 14 locations in the Southern California Bight (SCB) using passive acoustic moorings, AURALs, sampling at 8000 Hz from August through October 2007. Three low frequency (<900 Hz), short duration (<4 s) sounds were recorded in tanks containing only Bocaccio multiple times. One of these sounds was also commonly recorded in the SCB and is the same sound that was recorded first by Thompson off San Clemente Island in the 1960s. This sound exhibited the same diel pattern as noted by Thompson, with maximum calling at night, peaking at dusk and dawn. This long‐term persistence of the same sound indicates that passive acoustic tools may be used for efficient monitoring of changes in rockfish populations over long time periods.