Behavioral changes in the early stages of the larvae, can be a useful guide for fish breeders to determine the onset time of exogenous feeding, the quality and the suitability of the rearing conditions. The performance of hatchery including the type of incubator used for hatching the eggs and the high stocking density of the larvae, can cause stress and increase cortisol levels as stress index and affect the survival of larvae. Some unsaturated fatty acids, mainly docosahexaenoic acid (DHA), can affect specific behavioral features, such as aggregation behavior (schooling formation) in the initial larvae. Feeding on high levels of DHA by fish larvae can cause earlier aggregate behavior in larvae. DHA deficiency can cause abnormal swimming and decreased swim behavior in the schooling phase formation. The onset of exogenous feeding is accompanied by the completion of schooling behavior during daytime hours, dispersion of them in the bottom of the tank and completion of their yolk sac. Among the behaviors that larvae show, we can mention these cases: the upward movement towards the surface of the water with active drift of posterior trunk of the body and tail, then the non - active settlement of the larvae in the bottom, before start active swimming upward (negative geotaxis and drifting behavior), the initial early corner-gathering (non-dense school-like accumulation), pelagic and benthic swimming, accumulation of large numbers of pre - larvae in the tank corner (early corner - gathering), the high density accumulation of a large number of positive reotaxis school-like larvae in the tank bottom (rheotaxis schooling), accumulation of large numbers of larvae in the tanks corner (with slow water current), by active movement of the trunk and tail to the center of the tank (non-reotaxis behavior) and the dispersed and distributed at the tank bottom, with slow movement and without activity, is a sign of the onset of post schooling behavior. Other behaviors observed during the larval stage include phototaxis (attraction to light) and cannibalism the latter being particularly pronounced in more carnivorous and voracious species, such as the beluga sturgeon. Cannibalism tends to occur when larval food supplies are scarce and can result in significant larval mortality. Overall, it is essential to monitor larval behavior both from hatching until the onset of active feeding and during the active feeding phase to assess larval health and quality, evaluate rearing conditions, and determine the appropriate time to initiate exogenous feeding.
Ghorbani Vaghei, R. , Mohseni, M. , Pajand, Z. and Sohrabi, T. (2026). The importance of sturgeon larval behavior recognition in improving their farming management. Sturgeon Extention Journal, 9(16), 11-25.
MLA
Ghorbani Vaghei, R. , , Mohseni, M. , , Pajand, Z. , and Sohrabi, T. . "The importance of sturgeon larval behavior recognition in improving their farming management", Sturgeon Extention Journal, 9, 16, 2026, 11-25.
HARVARD
Ghorbani Vaghei, R., Mohseni, M., Pajand, Z., Sohrabi, T. (2026). 'The importance of sturgeon larval behavior recognition in improving their farming management', Sturgeon Extention Journal, 9(16), pp. 11-25.
CHICAGO
R. Ghorbani Vaghei , M. Mohseni , Z. Pajand and T. Sohrabi, "The importance of sturgeon larval behavior recognition in improving their farming management," Sturgeon Extention Journal, 9 16 (2026): 11-25,
VANCOUVER
Ghorbani Vaghei, R., Mohseni, M., Pajand, Z., Sohrabi, T. The importance of sturgeon larval behavior recognition in improving their farming management. Sturgeon Extention Journal, 2026; 9(16): 11-25.
