caa a22 4500 469097159 CHVBK 20180323133034.0 cr unu---uuuuu 170328e19920201xx s 000 0 eng 10.1007/BF00317212 doi (NATIONALLICENCE)springer-10.1007/BF00317212 Bluegill growth as modified by plant density: an exploration of underlying mechanisms [Elektronische Daten] [Jacqueline Savino, Elizabeth Marschall, Roy Stein] Summary: Bluegill (Lepomis macrochira) growth varies inconsistently with plant density. In laboratory and field experiments, we explored mechanisms underlying bluegill growth as a function of plant and invertebrate density. In the laboratory, bluegills captured more chironomids (Chironomus riparius) than damselflies (Enallagma spp. and Ischnura spp.), but energy intake per time spent searching did not differ between damselfly and chironomid treatments. From laboratory data, we described prey encounter rates as functions of plant and invertebrate density. In Clark Lake, Ohio, we created 0.05-ha mesocosms of inshore vegetation to generate macrophyte densities of 125, 270, and 385 stems/m2 of Potamogeton and Ceratophyllum and added 46-mm bluegill (1/m2). In these mesocosms, invertebrate density increased as a function of macrophyte density. Combining this function with encounter rate functions derived from laboratory data, we predicted that bluegill growth should peak at a high macrophyte density, greater than 1000 stems/m2, even though growth should change only slightly beyond 100 stems/m2. Consistent with our predictions, bluegills did not grow differentially, nor did their use of different prey taxa differ, across macrophyte densities in the field. Bluegills preferred chironomid pupae, which were relatively few in numbers but vulnerable to predation, whereas more cryptic, chironomid larvae, which were associated with vegetation but were relatively abundant, were eaten as encountered. Bluegills avoided physid snails, which were abundant. Contrary to previous work, vegetation did not influence growth or diet of bluegill beyond relatively low densities owing to the interaction between capture probabilities and macroinvertebrate densities. Springer-Verlag, 1992 Feeding behavior nationallicence Preference nationallicence Structural complexity nationallicence Savino Jacqueline Ohio Cooperative Fish and Wildlife Research Unit, Department of Zoology, The Ohio State University, 1735 Neil Ave., 43210, Columbus, OH, USA aut Marschall Elizabeth Ohio Cooperative Fish and Wildlife Research Unit, Department of Zoology, The Ohio State University, 1735 Neil Ave., 43210, Columbus, OH, USA aut Stein Roy Department of Zoology, The Ohio State University, 43210, Columbus, OH, USA aut Oecologia Springer-Verlag 89/2(1992-02-01), 153-160 0029-8549 89:2<153 1992 89 442 https://doi.org/10.1007/BF00317212 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00317212 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Savino Jacqueline Ohio Cooperative Fish and Wildlife Research Unit, Department of Zoology, The Ohio State University, 1735 Neil Ave., 43210, Columbus, OH, USA aut NATIONALLICENCE 700 1- Marschall Elizabeth Ohio Cooperative Fish and Wildlife Research Unit, Department of Zoology, The Ohio State University, 1735 Neil Ave., 43210, Columbus, OH, USA aut NATIONALLICENCE 700 1- Stein Roy Department of Zoology, The Ohio State University, 43210, Columbus, OH, USA aut NATIONALLICENCE 773 0- Oecologia Springer-Verlag 89/2(1992-02-01), 153-160 0029-8549 89:2<153 1992 89 442 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer