Summary Stable isotope analyses coupled with mixing models are being used increasingly to evaluate ecological management issues and questions. Such applications of stable often require simultaneous carbon nitrogen from the same sample. Correction values take account varying content 13 C‐depleted lipids is then frequently achieved by a lipid‐normalization procedure using model describing relationship between change in δ C following lipid removal original C:N ratio We evaluated applicability...

Abstract Apex predators play a key role in ecosystem stability across environments but their numbers general are decreasing. By contrast, European catfish ( Silurus glanis ), the freshwater apex predator, is on increase. However, studies concerning freshwaters scarce comparison to those terrestrial and marine ecosystems. The present study combines stomach content stable isotope analyses with diet preferences of reveal its impact since stocking. Catfish niche width extremely wide typical...

Abstract Understanding marine ecosystem structure and functioning is crucial in supporting sustainable management of natural resources monitoring the health ecosystems. The current study utilized stable isotope (SI) mixing models trophic position to examine energy flow, relationships, benthic‐pelagic coupling between food web components. Roughly 1900 samples from different levels web, collected during 2001–2010 four northern central sub‐basins Baltic Sea, were analyzed for SI ratios carbon...

The feeding ecology and ontogeny of a large size range brown trout Salmo trutta in Lake Fyresvatnet, southern Norway, were examined by stomach content stable isotope analyses. According to the contents, S. changed their diet at c. 30 cm total length ( L T ). smaller classes fed on benthic invertebrates surface insects, whereas larger (>30 cm) mainly whitefish Coregonus lavaretus . A similar, but more gradual shift piscivory 25–30 was found when using mixing model SIAR reveal dietary...

Summary The rate of non‐native fish introductions into freshwater ecosystems has more than doubled during the past three decades, posing a serious threat to native biodiversity. Despite potential benefits for fisheries, little is known about how introduced species interact with communities at food‐web level, or impact energy transfer dynamics and accumulation contaminants in lake ecosystems. Here, we explored trophic structure large, oligotrophic subarctic assessed niche use ecosystem‐wide...

Adaptive radiation is considered an important mechanism for the development of new species, but very little known about role thermal adaptation during this process. Such should be especially in poikilothermic animals that are often subjected to pronounced seasonal temperature variation directly affects metabolic function. We conducted a preliminary study individual lifetime habitat use and respiration rates four whitefish (Coregonus lavaretus (L.)) morphs (two pelagic, one littoral...

Abstract Conventional tags applied to individuals have been used investigate animal movement, but these methods require tagged be recaptured. Maps of regional isotopic variability known as “isoscapes” offer potential for various applications in migration research without tagging wherein isotope values tissues are compared environmental values. In this study, we present the spatial oxygen ( ) and dissolved inorganic carbon (δ 13 C DIC Baltic Sea water. We also provide an example how isoscapes...

Abstract Torniainen, J., Vuorinen, P. Jones, R. I., Keinänen, M., Palm, S., Vuori, K. A. and Kiljunen, M. 2014. Migratory connectivity of two Baltic Sea salmon populations: retrospective analysis using stable isotopes scales. – ICES Journal Marine Science, 71: 336–344. refers to the extent which individuals a migratory population behave in unison, has significant consequences for ecology, evolution conservation animals. We made assessment River Simojoki Kymijoki populations Atlantic Salmo...

Abstract The number of herbivores in populations ectothermic vertebrates decreases with increasing latitude. At higher latitudes, fish consuming plant matter are exclusively omnivorous. We assess whether omnivorous readily shift to herbivory or animal prey is typically preferred. address temperature as the key factor causing their absence at latitudes and discuss potential poleward dispersion caused by climate changes. A controlled experiment illustrates that rudd ( Scardinius...

Generalist species commonly have a fundamental role in ecosystems as they can integrate spatially distinct habitats and food-web compartments, well control the composition, abundance behavior of organisms at different trophic levels. populations typically consist specialized individuals, but potential for hence degree individual niche variation be largely determined by habitat complexity. We compared within three generalist fishes between two comparable lakes Czech Republic differing...

Abstract Wildlife inhabiting environments contaminated by radionuclides face putative detrimental effects of exposure to ionizing radiation, with biomarkers such as an increase in DNA damage and/or oxidative stress commonly associated radiation exposure. To examine the on gene expression wildlife, we conducted a de novo RNA sequencing study liver and spleen tissues from rodent, bank vole Myodes glareolus . Bank voles were collected Chernobyl Exclusion Zone (CEZ), where animals exposed...

Predatory fish have occasionally been observed preying on birds, sometimes repeatedly, but few studies were able to unravel the overall significance of avian prey in diet and predation impacts bird populations. We used a control/impact study setup, using Nature Reserve northern Italy nearby control area, determine: 1) contribution waterbirds wels catfish Reserve, 2) population density area 3) potential waterbird depredation by trends. Our stable isotope Bayesian mixing model indicated that...

Several studies have shown that distinct compartments of lake ecosystems are coupled via transportation organic matter, nutrients and energy across habitat boundaries. Here we evaluate the potential invasive signal crayfish (Pacifastacus leniusculus (Dana)) to modify pathways in large boreal lakes. Using a stable isotope mixing model calculation isotopic niches estimated contribution different food sources diets captured from habitats, inferred their transport littoral-profundal gradient....

Arctic charr and European whitefish are considered to be strong competitors in lakes, with the latter usually being superior species. However, high niche plasticity lake morphometry may suggestively facilitate resource partitioning coexistence between whitefish. Here, we explore trophic utilization (diet habitat use) of co-occurring brown trout deep oligotrophic Lake Fyresvatnet, southern Norway (59°05'N, 8°10'E). Using CPUE, stomach contents stable isotope analyses, a distinct was revealed...

Abstract Climate warming and consequent greening of subarctic landscapes increase the availability organic carbon to detrital food webs in aquatic ecosystems. This may cause important shifts ecosystem functioning through functional feeding patterns benthic organisms that rely differently on climatically altered resources. Twenty‐five lakes Finnish Lapland across a tree line ecotone were analysed for limnological optical variables, (δ 13 C) nitrogen 15 N) stable isotope ( SI ) composition...

This study investigated stock-specific variation in selected ecophysiological variables during the feeding migrations of Atlantic salmon Salmo salar Baltic Sea. Oxidative stress biomarkers and EROD (ethoxyresorufin-O-deethylase, Cyp1A enzyme) activity were used as indicators possible environmental stable isotopes determinants diet trophic position. Latvian S. stocks Daugava Gauja had distinct stable-isotope signatures compared to other stocks, indicating differences migration patterns,...

The Baltic Sea ecosystem and fish stocks contain high concentrations of environmental chemicals such as polychlorinated dibenzo-p-dioxins dibenzofurans (PCDD/Fs), biphenyls (PCBs). This study forecasts how changes in fishing or natural mortality would probably influence PCDD/F PCB the Bothnian (Northern Baltic) herring (Clupea harengus L.). An age-structured simulation model was developed to forecast stock dynamics, catches, weight-at-age under different assumptions about exploitation...

Introductions of grass carp, well known for their potentially negative ecosystem effects, have been performed in several countries around the world.As species was considered unable to reproduce naturally under non-native environmental conditions, little attention initially given its invasive potential.We studied an area northern-Italy where, contrary expectations, introductions that were early 80s still exert a considerable pressure on aquatic macrophytes.In order reveal whether observed...

Abstract Lake restoration by biomanipulation or phosphorus fixation has been commonly applied methods to improve the ecological status of lakes. However, effects lake on food-web dynamics are still poorly understood, especially when and nutrient used simultaneously. This study investigated combined a 70% fish removal (mainly roach ( Rutilus rutilus Linnaeus, 1758) bream Abramis brama Phoslock® treatment trophic ecology in Lyngsø (area: 9.6 ha, mean depth: 2.6 m), Denmark. The resulted...