[OANNES Foro] Otolith increment width responses to sudden changes in food levels: the importance of feeding history

[Mario Cabrejos]

Journal of Fish Biology
Volume 73 Issue 4, Pages 853 - 860
Published Online: 15 Sep 2008

Otolith increment width responses of juvenile Australian smelt Retropinna semoni to sudden changes in food levels: the importance of feeding history
Z. Tonkin? Tel.: +61 39450 8660; fax: +61 39450 8799; email: zeb.tonkin en dse.vic.gov.au, A. J. King? D. S. L. Ramsey? 
 ? Freshwater Ecology, Arthur Rylah Institute for Environmental Research, Department of Sustainability and Environment, P. O. Box 137, Heidelberg, Victoria 3084, Australia 

ABSTRACT
To aid the interpretation of otolith microstructure in wild fishes, the present study assessed responses in daily otolith increment widths of early juvenile Australian smelt Retropinna semoni to sudden changes in feeding conditions. There was an almost immediate response in otolith increment widths (which can be interpreted as growth in length) to sudden changes in feeding conditions, with such changes being detected statistically after c. 4 days. Fish displayed compensatory growth when food supplies were increased following a period of limited food, indicating the magnitude of the response in growth appears highly dependant on feeding history. Additionally, fish size also appeared to influence increment widths suggesting that both fish size and feeding history are important factors that must be considered when interpreting otolith microstructure for the species.