caa a22 4500 606226958 CHVBK 20210128101155.0 cr unu---uuuuu 210128e20150601xx s 000 0 eng 10.1007/s10641-015-0379-3 doi (NATIONALLICENCE)springer-10.1007/s10641-015-0379-3 Nonlinear and density-dependent fish habitat selection across physiochemical gradients in an invasive macrophyte habitat [Elektronische Daten] [Kyle Wilson, Micheal Allen, Robert Ahrens, Michael Netherland] Invasive macrophytes drive substantial changes to freshwater fish habitats. Such changes can influence how fish select for habitats, but fish-habitat relationships in many invasive macrophytes are often poorly understood at micro-scales. Fish habitat use is influenced by dissolved oxygen (DO) and habitat complexity, but this response can be nonlinear and dependent upon fish density. This study tested whether microhabitat use of sunfish (Lepomis spp.) in invasive macrophyte beds was density-dependent. Fish were sampled with underwater video point counts in six 0.405ha experimental ponds with surface-matted hydrilla Hydrilla verticillata and stocked with varying densities of sunfishes. Regression models were used to evaluate the key drivers for fish habitat selection across DO, complexity and fish densities. Both fish occurrence and fish counts were positively influenced by DO and negatively influenced by habitat complexity, but the fish counts-DO relationship was dome-shaped and both fish occurrence and counts depended upon fish densities. For example, at high fish densities, fish used low and high DO and high macrophytecomplexity; at low fish densities, fish avoided such areas. Fish counts peaked at intermediate DO and low macrophytecomplexity. Density-dependent fish habitat selection appeared to mitigate detrimental effects of invasive macrophytes on fish habitats, indicating that fish can and do use ‘inhospitable' habitats with potential positive population growth. Understanding density-dependent habitat selection is needed when evaluating the quality of habitats, as apparently inhospitable habitats can be utilized when fish density is high. Springer Science+Business Media Dordrecht, 2015 Lepomis macrochirus nationallicence Hydrilla verticillata nationallicence Aquatic plant management nationallicence Fish-macrophyte relationships nationallicence Freshwater fisheries nationallicence Underwater video nationallicence Wilson Kyle School of Forest Resources and Conservation, Program of Fisheries and Aquatic Sciences, University of Florida, 7922 NW 71st St., 32653, Gainesville, FL, USA aut Allen Micheal School of Forest Resources and Conservation, Program of Fisheries and Aquatic Sciences, University of Florida, 7922 NW 71st St., 32653, Gainesville, FL, USA aut Ahrens Robert School of Forest Resources and Conservation, Program of Fisheries and Aquatic Sciences, University of Florida, 7922 NW 71st St., 32653, Gainesville, FL, USA aut Netherland Michael US Army Engineer Research and Development Center, 7922 NW 71st Street, 32653, Gainesville, FL, USA aut Environmental Biology of Fishes Springer Netherlands 98/6(2015-06-01), 1525-1539 0378-1909 98:6<1525 2015 98 10641 https://doi.org/10.1007/s10641-015-0379-3 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10641-015-0379-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Wilson Kyle School of Forest Resources and Conservation, Program of Fisheries and Aquatic Sciences, University of Florida, 7922 NW 71st St., 32653, Gainesville, FL, USA aut NATIONALLICENCE 700 1- Allen Micheal School of Forest Resources and Conservation, Program of Fisheries and Aquatic Sciences, University of Florida, 7922 NW 71st St., 32653, Gainesville, FL, USA aut NATIONALLICENCE 700 1- Ahrens Robert School of Forest Resources and Conservation, Program of Fisheries and Aquatic Sciences, University of Florida, 7922 NW 71st St., 32653, Gainesville, FL, USA aut NATIONALLICENCE 700 1- Netherland Michael US Army Engineer Research and Development Center, 7922 NW 71st Street, 32653, Gainesville, FL, USA aut NATIONALLICENCE 773 0- Environmental Biology of Fishes Springer Netherlands 98/6(2015-06-01), 1525-1539 0378-1909 98:6<1525 2015 98 10641