Effects of light intensity, tank colour and photoperiod on swimbladder inflation success in larval striped bass, Morone saxatilis (Walbaum)

Abstract

Striped bass, Morone saxatilis (Walbaum), larvae, although physoclistous as adults, initially need to inflate their swimbladders by passing ingested air through a pneumatic duct to the swimbladder. Failure to inflate the swimbladder results in swimbladder atrophy, dysfunctional buoyancy control, deformities, and poor larval survival and growth. The present investigation studied the effects of light intensity, tank colour and photoperiod on the initial swimbladder inflation success of striped bass. In the first experiment, newly hatched larvae were reared for 2 weeks in black or white 350‐L circular tanks exposed to incandescent lighting at 163 or 10 lux. Larvae were fed Artemia from 6 days post‐hatching (dph). The standard length, and oil globule and yolk areas were measured. Swimbladder condition and evidence of feeding were recorded. To study the effects of photoperiod on inflation, larvae were reared in black tanks exposed to either 8 h:16 h or 16 h:8 h light:dark photoperiods at 139 lux. Striped bass inflated their swimbladders between 6 and 9 dph at 17 oC. Inflation success was significantly higher in black tanks (65%) compared with white tanks (42%), but light intensity did not significantly affect swimbladder inflation. Larval growth and food consumption were better in black tanks, primarily because this treatment resulted in more larvae with inflated swimbladders, although larvae with uninflated swimbladders in black tanks were longer at 12 dph than larvae with inflated swimbladders in white tanks. Larvae that successfully inflated their swimbladders fed earlier and exhibited better growth than larvae with noninflated swimbladders. Larvae reared at higher light intensities used up yolk reserves faster. Exposing striped bass larvae to 8 h:16 h light:dark photoperiods resulted in higher inflation rates (55%) compared to larvae reared at 16 h:8 h light:dark photoperiods (30%). Therefore, black tanks and short photoperiods are preferable for early rearing of striped bass larvae to maximize swimbladder inflation success.

Combined effects of rearing density and tank colour on the growth and welfare of juvenile white sea bream Diplodus sargus L. in a recirculating water system

“…Black tank colour proved to have a clear negative effect on juvenile D. sargus growth. For larval rearing of several marine species [turbot Scophthalmus maximus L., Howell 1979; stone flounder Kareius bicoloratus (Basilewsky), Matsuda, Tsujigado & Yanakawa 1987; gilthead sea bream S. aurata , Chatain & Ounais‐Guschemann 1991; striped bass Morone saxatilis (Walbaum), Martin‐Robichaud & Peterson 1998], a black or dark‐coloured background has been recommended as being better suited to reproduce a natural illumination environment (Naas, Huse & Iglesias 1996). Nevertheless, where juveniles are concerned, as well as rather long‐term background adaptation, black colour has been reported to reduce fish growth performance (common carp Cyprinus carpio L., Papoutsoglou et al 2000; barfin flounder Verasper moseri (Jordan and Gilbert), Yamanome, Amano and Takahashi 2005; rainbow trout Oncorhynchus mykiss (Walbaum), Papoutsoglou et al 2005).…”

Effects of background colour on growth indices and stress of young sterlet ( Acipenser ruthenus ) in a closed circulated system

“…Different coloured backgrounds can induce a variety of responses in relation to food intake, growth, survival and stress as shown for various species, such as tiger puffer Takifugu rubripus (Hatanaka 1997), scaled carp Cyprinus carpio (Papoutsoglou, Mylonakis, Miliou, Karakatsouli & Chadio 2000) and crabs (Rabbani & Zeng 2005), under specific rearing conditions. Several fish species prefer dark tank walls (Ostrowski 1989;Naas, Huse & Iglesias 1996) as they promote a suitable contrast between the prey and the background colour (Browman & Marcotte 1987), enhancing food intake that results in decrease in food consumption, costs and environmental pollution (Martin-Robichaud & Peterson 1998). Certain fish such as grouper, herring and turbot prefer black and darker colour background and exhibit better performances and immunity (Gilham & Baker 1985).…”

Effects of Tank Wall Color and Up‐welling Water Flow on Growth and Survival of Eurasian Perch Larvae (Perca fluviatilis)

“…Vision is of vital importance in food detection in Eurasian perch larvae (Dabrowski 1982), and factors like prey color and mobility, tank color, and lighting conditions may therefore improve the visual detection of prey (Hinshaw 1985; Utne 1997; Utne‐Palm 1999). High visual contrast of prey items, achieved by dark background, improved prey consumption in larvae of both yellow perch ( P. flavescens ) and striped bass ( Morone saxatilis ) (Hinshaw 1985; Martin‐Robichaud and Peterson 1998). However, the consumption rate of the fish larvae is also affected by intrinsic behavioral characteristics of both prey and predator.…”