Effects of littoral habitat complexity and sunfish composition on fish production |
| |
| Authors: | M. P. Carey K. O. Maloney S. R. Chipps D. H. Wahl |
| |
| Affiliation: | 1. Present address: NOAA Fisheries, Northwest Fisheries Science Center, 2725 Montlake Boulevard East, Seattle, WA 98112, USA.;2. Present address: Smithsonian Environmental Research Center, PO Box 28, Edgewater, MD 21037‐0028, USA.;3. Present address: U.S. Geological Survey, South Dakota Cooperative Fish and Wildlife Research Unit, SNP 138, Box 2140B, South Dakota State University, Brookings, SD 57007‐1696, USA.;4. Kaskaskia Biological Station, Illinois Natural History Survey, Rural Route 1, Box 157, Sullivan, IL 61951, USA |
| |
| Abstract: | Carey MP, Maloney KO, Chipps SR, Wahl DH. Effects of littoral habitat complexity and sunfish composition on fish production. Ecology of Freshwater Fish 2010: 19: 466–476. © 2010 John Wiley & Sons A/S Abstract – Habitat complexity is a key driver of food web dynamics because physical structure dictates resource availability to a community. Changes in fish diversity can also alter trophic interactions and energy pathways in food webs. Few studies have examined the direct, indirect, and interactive effects of biodiversity and habitat complexity on fish production. We explored the effects of habitat complexity (simulated vegetation), sunfish diversity (intra‐ vs. inter‐specific sunfish), and their interaction using a mesocosm experiment. Total fish production was examined across two levels of habitat complexity (low: 161 strands m?2 and high: 714 strands m?2) and two sunfish diversity treatments: bluegill only (Lepomis macrochirus) and bluegill, redear sunfish (Lepomis microlophus), and green sunfish (Lepomis cyanellus) combination. We also measured changes in total phosphorus, phytoplankton, periphyton, and invertebrates to explain patterns in fish production. Bluegill and total fish production were unaffected by the sunfish treatments. Habitat complexity had a large influence on food web structure by shifting primary productivity from pelagic to a more littoral pathway in the high habitat treatments. Periphyton was higher with dense vegetation, leading to reductions in total phosphorus, phytoplankton, cladoceran abundance and fish biomass. In tanks with low vegetation, bluegill exhibited increased growth. Habitat complexity can alter energy flow through food webs ultimately influencing higher trophic levels. The lack of an effect of sunfish diversity on fish production does not imply that conserving biodiversity is unimportant; rather, we suggest that understanding the context in which biodiversity is important to food web dynamics is critical to conservation planning. |
| |
| Keywords: | habitat complexity sunfish species food webs fish production |
|
|
