plSSN : 0374-8111 | elSSN : 2287-8815
plSSN : 0374-8111 | elSSN : 2287-8815
plSSN : 0374-8111elSSN : 2287-8815
Analysis of Spawning-Season Chorus Characteristics and Diel VocalizationPatterns of Small Yellow Croaker Larimichthys polyactis and BrownCroaker Miichthys miiuy
김한수·조성호·김선효·강돈혁·김병권1·윤영글*
한국해양과학기술원 해양력강화·방위연구부, 1㈜시스코어
This study quantified the chorus characteristics of two sciaenid species, small yellow croaker Larimichthys polyactis and brown croaker Miichthys miiuy, during their spawning seasons using passive acoustic monitoring. Continuous recordings were collected using an autonomous recorder at a sea-cage facility in Tongyeong, Korea. The small yellow croaker was monitored from 15-30 June 2025, and brown croaker from 15-30 September 2025. Power spectral density (PSD) and empirical probability density (EPD) analysis revealed that both species showed strong energy below 1 kHz, but with distinct chorus formations and diel rhythms. Small yellow croaker produced long-lasting nocturnal choruses spanning 0.3-1.2 kHz from evening to dawn, with daily maximum sound pressure levels (SPL) of approximately 135-140 dB re 1 μPa. Brown croaker produced shorter, temporally focused choruses after sunset within 0.2-1.0 kHz, with maximum SPL of 125-140 dB re 1 μPa. EPD results indicated enhanced mean PSD and higher percentiles during high-activity periods for both species. These findings demonstrate species-specific diel vocal strategies, highlighting spawning choruses as key biological components of the marine soundscape and useful acoustic indicators for soundscape-based monitoring of coastal fish populations.
Fish chorus, Small yellow croaker, Brown croaker, Diel pattern, Passive acoustic monitoring