Year‐round natural spawning, early development, and the effects of temperature, salinity and prey density on captive ornate gobyIstigobius ornatus(Rüppell, 1830) larval survival

Abstract

Natural spawning, early development and larviculture of the ornate goby Istigobius ornatus in captivity were studied for the first time. I. ornatus spawned 46 times from 31 October 2013 to 31 October 2014. Fecundity ranged from 246 to 10,214 eggs per clutch, with an average hatching rate of 77.8% ± 9.9% (M ± SEM). Fertilized eggs (1.31-1.54 × 0.46-0.50 mm in diameter) were adhesive demersal and oval-shaped.Embryonic development lasted 84 hr at 27.5 ± 0.5°C. Newly hatched larvae [2.12 ± 0.04 mm in total length (TL)] transformed to the juvenile stage completely when TL was 7.79 mm. Effects of different water temperatures (24, 28 and 32°C) and salinities (10, 15, 20, 25, 30, 35 and 40 g/L) on per cent survivals (%) and survival activity indices (SAIs) were tested. Survival was not significantly different under different temperatures; SAIs was significantly higher at 28°C. Larvae showed the significantly higher survival and SAIs at salinities 10-30 g/L than at 35 and 40 g/L.Effect of different prey densities on survival was significantly higher in 7 days post hatch larvae fed 20 and 30 rotifers/ml. These findings could guide future programs in captive breeding technology development and commercial production of other marine ornamental gobies. K E Y W O R D S early development, Istigobius ornatus, larviculture, marine ornamentals, spawning, survival activity index How to cite this article: Chiu P-S, Leu M-Y, Meng P-J. Yearround natural spawning, early development, and the effects of temperature, salinity and prey density on captive ornate goby Istigobius ornatus (Rüppell, 1830) larval survival. Aquac

Matrilineal evidence for genetic structure and Late Pleistocene demographic expansion of the Ornate goby Istigobiusornatus (Teleostei: Gobiidae) in the Persian Gulf and Oman Sea

“…The Fst estimates were not different from zero for population pairs from the Persian Gulf, implying that gene flow among these populations was common, most probably caused by larval dispersion. The fertilized eggs of I. ornatus are adhesive, demersal with attachment filaments but they have a planktonic life stage in their larval period (Chiu et al., 2018; Patzner et al., 2012). This life history trait of the Ornate goby can affect its genetic and population structure (Akihito et al., 2000; Chiu et al., 2018).…”

“…The fertilized eggs of I. ornatus are adhesive, demersal with attachment filaments but they have a planktonic life stage in their larval period (Chiu et al., 2018; Patzner et al., 2012). This life history trait of the Ornate goby can affect its genetic and population structure (Akihito et al., 2000; Chiu et al., 2018). Therefore, passive transport of larvae through marine currents might also have contributed to the dispersion of I. ornatus .…”

“…It is thus an interesting species to examine its intraspecific genetic structure. Istigobius ornatus is a benthic species that inhabits marine and brackish areas such as lower estuaries, mangroves, silty and muddy zones as well as crevices or interstices in rocky substrates; it is both detritivorous and carnivorous (Chiu et al., 2018; Cole, 1990). Individuals of this species can be found in very shallow waters (0–2 m) and often accumulate at low tide at the margin of the water, while at high tide they hide in submerged burrows (Murdy & Hoese, 1985).…”

First feeding of a marine ornamental fish, the White‐barred Goby Amblygobius phalaena: Investigating the optimal initial live feed organisms and optimal feeding density

“…The rearing of larval fish presents significant challenges due to their small and delicate nature, susceptibility to changes in water quality, and specific dietary requirements compared to juvenile or adult fish (Yúfera and Darias 2007;Dhaneesh et al 2012;Madhu et al 2016). When addressing dietary needs, previous research has highlighted two critical factors for the successful rearing of these fragile marine ornamental fish larvae: the selection of appropriate live feed organisms during the first feeding stage (Leu et al 2015(Leu et al , 2022Chen et al 2020;Chiu and Leu 2021) and the maintenance of an optimal prey density or concentration (Moorhead and Zeng 2011;Degidio et al 2017;Majoris et al 2018;Chiu et al 2019).…”

“…Rotifers have been commonly used as initial live feed organisms because they can be cultured at high densities and their nutritional value can be enhanced through enrichment (Lubzens and Zmora 2003;Conceição et al 2010). Various marine ornamental fish species, such as clownfishes (Olivotto et al 2008), gobies (Majoris et al 2018;Chiu et al 2019), and blennies (Moorhead and Zeng 2011;, have been successfully raised using rotifers as their initial live prey. However, some species with tiny mouth sizes, such as the Dwarf Hawkfish Cirrhitichthys falco (Chiu and Leu 2021), Milletseed Butterflyfish Chaetodon miliaris (Degidio et al 2017), surgeonfishes (DiMaggio et al 2017Callan et al 2018;Sowaske et al 2023), and wrasses (Groover et al 2021;Leu et al 2022), are not suitable for feeding on rotifers (size = 100-250 μm).…”