Govedic M. 2001.

Prehrana kormorana (Phalacrocorax carbo) na obmocju reke Save od Ljubljane do Zagorja (Slovenija). Dipl. delo. Ljubljana, Univ. v Ljubljani, Biotehniška fakulteta, Odd. za biologijo. NO XIII, 115 p., 29 tab., 18 graph, 4 fig., 258 ref. -

[Diets of cormorants (Phalacrocorax carbo) in region of Sava river between Ljubljana and Zagorje (Slovenia)]. Graduation Thesis, University of Ljubljana, Slovenia.

Summary: Diet of cormorants (Phalacrocorax carbo) was studied in the region of the Sava river between Ljubljana and Zagorje in winter 1998/99 by pellet analysis (n=473). Cormorants were observed on feeding places and number of them was attended. Among 12 fish species found in cormorants' pellets Cyprinidae were most frequent (85,8 % by number, 90,5 % by biomas). Inside them chub (Leuciscus cephalus) with 16,4 % by number and 38,6 % by biomas and nase (Chondrostoma nasus) with 3,9 % by number and 16,5 % by biomas were most frequent. Length of preyed fish was from 23 to 345 mm. Small fish (<10 g) formed 46,3 % by number and 3,6 % by biomas and big fish (> 150 g) formed 9,1 % by number and 47,4 % by biomas. In region there were 64.287 cormorants feeding days. Number of cormorants was the highest in january (2,13 individual/ha). The correction factors were used for calculating fish lengths. They were calculated by comparing the regresion lines between structures from reference colection, wich was made, and structures from pellets.

Keywords: Cormorant - Phalacrocorax carbo - wintering - diet - pellet analysis - Sava river - Slovenia

Address: Marijan Govedic marijan.govedic@ckff.si

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