Are salmon-derived nutrients being incorporated in food webs of invaded streams? Evidence from southern Chile
نویسندگان
چکیده
Using stable isotope analyses of N and C we present preliminary evidence of marine-derived nutrients from introduced Chinook salmon (Oncorhynchus tshawytscha Walbaum) in stream food webs of Laguna Los Patos, NW Patagonia. Similar to values reported within Chinook salmon's native distributional range periphyton and aquatic insects are the trophic levels that show the greatest enrichment of δ15N (5–6‰). Since there is a rapid expansion of Chinook salmon in South America future effort is needed to elucidate the mechanisms and consequences of nutrients subsidies from salmon carcasses in those invaded ecosystems.
منابع مشابه
Effects of Salmon-Derived Nutrients and Habitat Characteristics on Population Densities of Stream-Resident Sculpins
Movement of nutrients across ecosystem boundaries can have important effects on food webs and population dynamics. An example from the North Pacific Rim is the connection between productive marine ecosystems and freshwaters driven by annual spawning migrations of Pacific salmon (Oncorhynchus spp). While a growing body of research has highlighted the importance of both pulsed nutrient subsidies ...
متن کاملFertilization of terrestrial vegetation by spawning Pacific salmon: the role of flooding and predator activity
Spawning Pacific salmon (Onchorhynchus) transport marine-derived nutrients into streams and rivers. Subsequently, these marine-derived nutrients are incorporated into freshwater and terrestrial food webs through decomposition and predation. In this study, we investigated the influence of spawning Pacific salmon on terrestrial vegetation using stable isotope analysis. We hypothesized that terres...
متن کاملEvaluating the consequences of salmon nutrients for riparian organisms: Linking condition metrics to stable isotopes
Stable isotope ratios (δ13C and δ15N) have been used extensively to trace nutrients from Pacific salmon, but salmon transfer more than carbon and nitrogen to stream ecosystems, such as phosphorus, minerals, proteins, and lipids. To examine the importance of these nutrients, metrics other than isotopes need to be considered, particularly when so few studies have made direct links between these n...
متن کاملAquatic food webs
~ Organic matter from aquatic and terrestrial sources provides the carbon energy that 'drives' aquatic food webs. Most streams and rivers are heterotrophic — that is, more carbon is consumed (e.g. by animals and bacteria) than is produced within the system by aquatic plants. However, despite the presence of vast amounts of carbon in streams and rivers, only a small proportion of the total is tr...
متن کاملMarine Subsidies in Freshwater Ecosystems: Salmon Carcasses Increase the Growth Rates of Stream-Resident Salmonids
—We tested the hypotheses that marine-derived resource subsidies (salmon carcasses) increase the growth rates of stream-resident salmonids in southeastern Alaska and that more carcasses translate into more growth. Five carcass treatments of pink salmon Oncorhynchus gorbuscha (0, 1, 2, 3, and 4 carcasses/m2 or 0, 1.9, 3.7, 5.6, and 7.4 kg wet mass/m2) were replicated six times in once-through ar...
متن کامل