First report on the diet and reproductive biology of red-toothed triggerfishOdonus niger(Ruppell, 1836) from the south-eastern Arabian Sea

Abstract

The feeding habits and reproductive biology of red-toothed triggerfish Odonus niger (Ruppell, 1836) was analysed from 449 specimens collected from the Karnataka coast of the south-eastern Arabian Sea. Of the total stomachs examined, only 54 (12%) were empty and 395 contained food remains. The diet comprised crustacean remains (48.0%), zooplankton (21.4%), algae (16.5%), fish remains (6.1%) and cephalopod remains (5.3%) along with partially digested matter (2.3%) and detritus (0.4%). The species was found to be a generalist feeder and an omnivore. The overall sex ratio between males and females (1: 0.44) was significantly (P < 0.05) different. Histological examination of the ovaries indicated asynchronous ovarian development in females, with males maturing earlier than females. The gonadosomatic index (GSI) patterns of males and females, and the presence of ripe ovaries and spermatozoids suggested that April–May is the peak spawning period. The absolute and relative fecundity estimates ranged from 16,464–312,420 eggs and 251–2812 eggs g−1 respectively. Fecundity was positively correlated with total length and body weight. The biological information on diet composition and reproductive traits provided for the first time in this study can facilitate conservation, management and sustainable exploitation of this species in the study area.

Queen Triggerfish Balistes vetula Age-Based Population Demographics and Reproductive Biology for Waters of the North Caribbean

“…The attributes of group synchronous oocyte development, batch spawning, and indeterminate fecundity combined with benthic nesting behaviors in triggerfishes may enable a high reproductive output for many triggerfish species, including queen triggerfish. In addition to queen triggerfish, reproductive histological assessments have been reported for gray triggerfish [19,65], black triggerfish Melichthys niger [66], and red-toothed triggerfish Odonus niger [67], with all three species also exhibiting group synchronous oocyte development, indeterminate fecundity, and batch spawning. All triggerfish species for which spawning behavior has been reported in the scientific literature are benthic nesters, and females can spawn multiple batches of eggs within a spawning season [4,19,41,42,66,67].…”

“…In addition to queen triggerfish, reproductive histological assessments have been reported for gray triggerfish [19,65], black triggerfish Melichthys niger [66], and red-toothed triggerfish Odonus niger [67], with all three species also exhibiting group synchronous oocyte development, indeterminate fecundity, and batch spawning. All triggerfish species for which spawning behavior has been reported in the scientific literature are benthic nesters, and females can spawn multiple batches of eggs within a spawning season [4,19,41,42,66,67]. In general, maternal care of offspring is rare among coral reef fishes with external fertilization [68,69] but is common in triggerfishes during the benthic nesting period, in which females care for their brood of fertilized eggs by guarding them against potential egg predators and caring for them via blowing on them and fanning them until just before the eggs hatch and larvae swim up to a planktonic life phase [38,39,[41][42][43].…”

Biochemical composition, protein quality and amino acid profile of red‐toothed triggerfish (Odonus niger), an underutilised fish

“…Fishes belonging to the family Balistidae constitute a substantial catch in certain areas. Among them, O. niger (Ruppell 1836) (Actinopterygii/Tetraodontiformes/Balistidae) commonly called red‐toothed triggerfish is a reef‐associated demersal fish species distributed extensively in the tropical Indo‐Pacific region at a depth of 5–40 m. It is locally known as ‘ Kargilmeenu’ , ‘ Klaati’ or ‘ Kappuhandi’ in Karnataka, India (Suyani et al ., 2021a). It is one of the unconventional trash fish commercially available along the southwest coast of India (Ramachandran & Philip, 2010).…”

“…It is one of the unconventional trash fish commercially available along the southwest coast of India (Ramachandran & Philip, 2010). Huge landings of triggerfish were observed in 2018, trawlers landed around 40–50 tonnes per fishing trip along the Karnataka coast, India (Suyani et al ., 2021a). The landings of O. niger in India during 2018 were 72 140 tonnes, out of which 58.1% were from Karnataka while the rest of the catch was reported from Maharashtra, Goa, Kerala on the west coast and Tamil Nadu on the east coast of India.…”