Seasonal and spatial fluctuations in Oncorhynchus trout diet in a temperate mixed-forest watershed
| Autor: | Douglas S. Bateman, Alan T. Herlihy, William J. Gerth, Judith L. Li, Richard Van Driesche |
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| Rok vydání: | 2016 |
| Předmět: |
0106 biological sciences
Biomass (ecology) geography geography.geographical_feature_category biology Ecology 010604 marine biology & hydrobiology Aquatic Science biology.organism_classification 010603 evolutionary biology 01 natural sciences Predation Fishery Trout Benthic zone Tributary Temperate climate Oncorhynchus Ecology Evolution Behavior and Systematics Invertebrate |
| Zdroj: | Canadian Journal of Fisheries and Aquatic Sciences. 73:1642-1649 |
| ISSN: | 1205-7533 0706-652X |
| DOI: | 10.1139/cjfas-2015-0520 |
| Popis: | To examine seasonal and spatial factors affecting prey consumption by Oncorhynchus trout, we examined trout diet from mainstem and tributary sites at Hinkle Creek, Oregon. Benthic invertebrate densities were similar across seasons and did not differ between tributaries and the mainstem. Fluctuations in diet followed seasonal changes in invertebrate sizes and abundances. Average prey biomass consumed was positively correlated with fish size. Consumption rates were high in spring and summer but fell significantly in fall when fewer and smaller prey were eaten. A switch in consumption from 36% terrestrial prey biomass in spring to 85% in summer coincided with an increase in terrestrial prey size and a decrease in benthic prey size. Location within the watershed also affected prey consumption. Despite similarities in diet composition, tributary trout consumed somewhat more biomass than trout in the mainstem but grew relatively slower. Because stream fishes such as Oncorhynchus trout feed opportunistically on varied prey, studies incorporating multiple seasons and stream types are important to understanding energy exchanges between terrestrial and aquatic ecosystems. |
| Databáze: | OpenAIRE |
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