Feeding habits of damselfishes (Pomacentridae) from the southern part of Taiwan

Abstract

In order to investigate the acquisition of the nocturnal feeding in juvenilesilver bream,Sparus sarba,two stages of juveniles with body length 12-15 mmand 30-40 mm were fed with Artemias nauplii under dark-adaptation.The preydensity was examined every 30-minute and continued for 150 minutes.Theoreticalcurve as a passive feeding was derived from N(subscript t)=N0(1－p)(superscript t)(Kawamuraand Hara,1980)and compared with that from the measured density.Chi-Square tests showed the significant differences in older juvenile stage,but nodifferences in younger stage.It is likely that older juveniles have acquiredsome sensory ability other than vision for their nocturnal feeding.Thereforethey can obtain food by actively searching under dark-adaptation.