Ž . Fisheries Research 34 1998 39–45 Feeding behaviour of whiting, Merlangius merlangus, L. in captivity K. Seyhan a, ) , D.J. Grove b , J. King b a Karadeniz Technical UniÕersity, Faculty of Marine Science, C ¸ amburnu-Trabzon, Turkey b School of Ocean Sciences, UniÕersity College of North Wales, Menai Bridge Laboratories, LL59 5EY, Menai Bridge, Anglesey, UK Accepted 3 September 1997 Abstract Ž . The feeding behaviour of medium sized 155.25 "27.98 cm, n s8 whiting, Merlangius merlangus, under laboratory conditions was investigated with continuous food availability. This investigation was made using both natural, Sprattus sprattus, and artificial diet which was monitored with a periodogram analysis obtained by a newly developed demand Ž . feeding unit. The return of appetite of large whiting 305.85 "056.90 cm was also studied. Medium size whiting consumed Ž . 5.29 g wet weight rday corresponding to 3.41% body weight, approximately three sprats of 1.88 g each. The return of appetite after a single meal was found to follow the gastric emptying curve closely. If food is not offered directly but made Ž . available through demand feeding, the whiting feed rhythmically every 21 h ; under these conditions, it was estimated that feeding activity returns when the stomach is 40% full. q 1998 Elsevier Science B.V. Keywords: Whiting; Merlangius merlangus; Experimental feeding 1. Introduction The nutritional components and gross energy made available for cell maintenance, growth, locomotion and reproduction are determined by the amount of food consumed. The relationship between fish and their food intake is affected by a complex interaction between a number of factors. Under conditions in which food is continually available, and in the absence of predators, the quan- ) Corresponding author. Tel.: q90 462 325 03 76; fax: q90 462 325 03 76; e-mail: seyhan@jbsd.ktu.edu.tr tity of food consumed, and perhaps also the pattern of consumption, may be expected to be limited only by digestive constraints on how much food can be processed in a day. Feeding rates determined under these conditions can be considered as the physio- Ž . logical maximum for a species Hall, 1987 . Further- more, daily feeding pattern may also represent an ideal pattern to which a wild population would con- form in the absence of environmental constraints. In this study, experiments were conducted to in- vestigate the maximum daily ration and pattern of food intake of whiting. Return of appetite after a satiation meal was also investigated. Finally a new demand feeding technique was developed and feed- ing behaviour in such conditions was investigated. 0165-7836r98r$19.00 q 1998 Elsevier Science B.V. All rights reserved. Ž . PII S0165-7836 97 00080-5