DBPapers
DOI: 10.5593/sgem2017/52/S20.099

RESEARCHES CONCERNING FOOD AND FEEDING BEHAVIOR OF PADDLEFISH (POLYODON SPATHULA, WALB. 1792) IN LANDSCAPED AQUATIC ECOSYSTEMS

M. Costache, M. Costache, C. Bucur, D. Radu, N. Marica
Wednesday 13 September 2017 by Libadmin2017

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgem.org, SGEM2017 Conference Proceedings, ISBN 978-619-7408-09-6 / ISSN 1314-2704, 29 June - 5 July, 2017, Vol. 17, Issue 52, 769-776 pp, DOI: 10.5593/sgem2017/52/S20.099

ABSTRACT

This paper presents results of research on feeding behavior of paddlefish (Polyodon spathula, Walb. 1792), performed at the Fish Culture Research and Development Station Nucet, Dâmboviţa, between 2002 -2007. The results confirmed the planctonofag character of this species. Paddlefish food consists primarily of zooplankton, insects and insect larvae, plant debris and detritus, identified in the intestinal contents. Feeding behavior is differentiated by age and size of fish. During the first days of life, juvenile paddlefish feeds active on zooplankton exclusively by hunting and capture. After about 30-35 days the juvenile paddlefish develop the filter apparatus, they feed by catching and filtering, depending on the density of zooplankton organisms. The filter apparatus of the paddlefish fry is fully developed and functional when they reach the size of about 400 mm. From this size paddlefish fry start feeding exclusively by filtration. Analyzing the digestive tract content from paddlefish aged 3-8 years result that the trophic spectrum is generally the same. The dominance of a particular group of items is given by abundance in the growth medium. The presence of the high percentage of a group of zooplankton organisms in the digestive tract of paddlefish corresponds to their peak abundance in the aquatic environment. At the older ages paddlefish is less selective feeding.

Keywords: paddlefish, food, feeding behavior, aquatic ecosystems