caa a22 4500 469098376 CHVBK 20180323133038.0 cr unu---uuuuu 170328e19920401xx s 000 0 eng 10.1007/BF00317809 doi (NATIONALLICENCE)springer-10.1007/BF00317809 Are digestive characteristics important contributors to the profitability of prey? [Elektronische Daten] A study of diet selection in the fifteen-spined stickleback, Spinachia spinachia (L.) [Michel Kaiser, Andrew Westhead, Roger Hughes, Robin Gibson] Summary: In the field, Spinachia fed on four types of prey; copepods, isopods, mysids and amphipods. As fish size increased, mysids gradually succeeded amphipods as the most important food type in the diet. Prey dimensions and morphometry of the fish's mouth most accurately predicted capture efficiency for amphipods, whereas for mysids capture efficiency was determined by the prey's escape response and the fish's fast-start capability. Responses to model prey revealed the ability of fish to differentiate among contrasting prey characteristics, resulting in the adoption of appropriate predatory tactics. Amphipods were associated with a shorter gut evacuation time than mysids, although approximately equal proportions of energy were absorbed from each. Similar rations of mysids and amphipods were required to satiate fish. The lower energy content per unit dry mass of amphipods was off set by their lower water content. From pre-digestive behaviour, we predicted that mysids were more profitable than amphipods, and this was reflected in the fish's choice. Conversely, incorporating the net rate of energy uptake by the gut led us to predict that amphipods were more profitable. Although physiological constraints clearly influence the net rate of energy uptake, it appears that dietary preferences are based on pre-digestive predatory behaviour and hence on time minimisation. Springer-Verlag, 1992 Energy maximisation nationallicence Prey profitability nationallicence Diet selection nationallicence Handling time nationallicence Gut emptying time nationallicence Kaiser Michel Functional and Evolutionary Biology Group, School of Biological Sciences, University College of Wales, LL57 2UW, Bangor, UK aut Westhead Andrew Functional and Evolutionary Biology Group, School of Biological Sciences, University College of Wales, LL57 2UW, Bangor, UK aut Hughes Roger Functional and Evolutionary Biology Group, School of Biological Sciences, University College of Wales, LL57 2UW, Bangor, UK aut Gibson Robin Dunstaffnage Marine Laboratory, P.O. Box 3, PA34 4AD, Oban, Argyll, Scotland, UK aut Oecologia Springer-Verlag 90/1(1992-04-01), 61-69 0029-8549 90:1<61 1992 90 442 https://doi.org/10.1007/BF00317809 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00317809 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kaiser Michel Functional and Evolutionary Biology Group, School of Biological Sciences, University College of Wales, LL57 2UW, Bangor, UK aut NATIONALLICENCE 700 1- Westhead Andrew Functional and Evolutionary Biology Group, School of Biological Sciences, University College of Wales, LL57 2UW, Bangor, UK aut NATIONALLICENCE 700 1- Hughes Roger Functional and Evolutionary Biology Group, School of Biological Sciences, University College of Wales, LL57 2UW, Bangor, UK aut NATIONALLICENCE 700 1- Gibson Robin Dunstaffnage Marine Laboratory, P.O. Box 3, PA34 4AD, Oban, Argyll, Scotland, UK aut NATIONALLICENCE 773 0- Oecologia Springer-Verlag 90/1(1992-04-01), 61-69 0029-8549 90:1<61 1992 90 442 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer