Ecology of top fish predators, European catfish and asp, with consequences to fish communities

Mgr. Marek ŠMEJKAL

Doctoral thesis

Abstract:

The dissertation thesis focuses on predator ecology in artificial water bodies. Paper I deals with the importance of chemical cues for predator-prey interactions in an aquatic environment. Here, I demonstrate that the ability to detect chemical cues represents a survival benefit for prey species. Paper II points out gillnet methodological bias, which may have subsequent repercussions in field evaluation of a predator's presence and assessment of larger fish abundance in general. Papers III and IV focus on asp Leuciscus aspius spawning grounds. In Paper III, I demonstrate how males maximize their spawning chances by early arrival and in Paper IV, I evaluate the predation pressure of asp prey, Alburnus alburnus, directed on asp eggs.

Abstract:

The dissertation thesis focuses on predator ecology in artificial water bodies. Paper I deals with the importance of chemical cues for predator-prey interactions in an aquatic environment. Here, I demonstrate that the ability to detect chemical cues represents a survival benefit for prey species. Paper II points out gillnet methodological bias, which may have subsequent repercussions in field evaluation of a predator's presence and assessment of larger fish abundance in general. Papers III and IV focus on asp Leuciscus aspius spawning grounds. In Paper III, I demonstrate how males maximize their spawning chances by early arrival and in Paper IV, I evaluate the predation pressure of asp prey, Alburnus alburnus, directed on asp eggs.

Keywords

chemical cues, European catfish, asp, bleak, protandry, predator-prey reversal

Language used: English

Date on which the thesis was submitted / produced: 10. 8. 2017

Thesis defence

• Date of defence: 25. 9. 2017
• Supervisor: RNDr. Marie Prchalová, Ph.D.

UNIVERSITY OF SOUTH BOHEMIA IN ČESKÉ BUDĚJOVICE

Faculty of Science

Doctoral programme / field:
Biology / Hydrobiology