| Autor: |
Tunney TD; Center for Limnology, University of Wisconsin-Madison, N. Park St., Madison, WI, 53706, USA. Tyler.Tunney@dfo-mpo.gc.ca.; Fisheries and Oceans Canada, Gulf Fisheries Centre, P.O. Box 5030, 343 Université Ave, Moncton, NB, E1C 9B6, Canada. Tyler.Tunney@dfo-mpo.gc.ca., McCann KS; Department of Integrative Biology, University of Guelph, 50 Stone Rd. East, Guelph, ON, N1G 2W1, Canada., Jarvis L; Department of Integrative Biology, University of Guelph, 50 Stone Rd. East, Guelph, ON, N1G 2W1, Canada.; Department of Ecology and Evolution, University of Toronto, 25 Harbord St., Toronto, ON, M5S 3G5, Canada., Lester NP; Aquatic Research and Development Section, Ontario Ministry of Natural Resources, 2140 East Bank Dr., Peterborough, ON, K9J 7B8, Canada.; Department of Ecology and Evolution, University of Toronto, 25 Harbord St., Toronto, ON, M5S 3G5, Canada., Shuter BJ; Aquatic Research and Development Section, Ontario Ministry of Natural Resources, 2140 East Bank Dr., Peterborough, ON, K9J 7B8, Canada.; Department of Ecology and Evolution, University of Toronto, 25 Harbord St., Toronto, ON, M5S 3G5, Canada. |
| Abstrakt: |
Habitat coupling is a concept that refers to consumer integration of resources derived from different habitats. This coupling unites fundamental food web pathways (e.g., cross-habitat trophic linkages) that mediate key ecological processes such as biomass flows, nutrient cycling, and stability. We consider the influence of water transparency, an important environmental driver in aquatic ecosystems, on habitat coupling by a light-sensitive predator, walleye (Sander vitreus), and its prey in 33 Canadian lakes. Our large-scale, across-lake study shows that the contribution of nearshore carbon (δ 13 C) relative to offshore carbon (δ 13 C) to walleye is higher in less transparent lakes. To a lesser degree, the contribution of nearshore carbon increased with a greater proportion of prey in nearshore compared to offshore habitats. Interestingly, water transparency and habitat coupling predict among-lake variation in walleye relative biomass. These findings support the idea that predator responses to changing conditions (e.g., water transparency) can fundamentally alter carbon pathways, and predator biomass, in aquatic ecosystems. Identifying environmental factors that influence habitat coupling is an important step toward understanding spatial food web structure in a changing world. |
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