The Effects of Tank Color and Light Intensity on Growth, Survival, and Stress Tolerance of White Seabass, Atractoscion nobilis, larvae

Abstract

White seabass, Atractoscion nobilis, are important commercial and sport fish commonly found in Magdalena Bay, Baja California, Mexico to San Francisco Bay, California, USA (Thomas 1968). Adult white seabass inhabit the nearshore zone over rocky bottoms and kelp beds (Young 1973). White seabass can reach a size of 1.5 m and 38 kg (Miller and Lea 1972). Juveniles and young of the year are found in embayments and shallow water along the open coast (Allen and Franklin 1988a, b). White seabass are batch spawners typically spawning from April to August and congregate in rocky reef and kelp bed areas in the nearshore zone at this time (Thomas 1968). Eggs are approximately 1.3 mm in diameter and pelagic. Larvae are pelagic and are typical marine finfish larvae (Moser et al. 1983). Vision is important for feeding in most marine finfish larvae (Hunter 1980; Blaxter 1986). However, the eyes of marine finfish larvae at first feeding do not have illumination adaptation capability (Blaxter and Staines 1970; Neave 1984) and the development of the eye and visual acuity of white seabass, A. nobilis, is specifically known to be poor at first feeding (Margulies 1989). It is important to optimize environmental conditions in larviculture to facilitate feeding behavior (Tamazouzt et al. 2000). Maximization of feeding behavior should result in improved growth and survival (Downing and Litvak 1999b). Visually, this means maximizing contrast between food items and the environment making illumination in the larval rearing environment of primary importance. Illumination within a larval rearing tank can be affected by light source and intensity as well as tank color (Naas et al.