0000000000986566
AUTHOR
Mikko Kiljunen
Adaptive radiation along a thermal gradient: preliminary results of habitat use and respiration rate divergence among whitefish morphs.
Adaptive radiation is considered an important mechanism for the development of new species, but very little is known about the role of thermal adaptation during this process. Such adaptation should be especially important in poikilothermic animals that are often subjected to pronounced seasonal temperature variation that directly affects metabolic function. We conducted a preliminary study of individual lifetime thermal habitat use and respiration rates of four whitefish (Coregonus lavaretus (L.)) morphs (two pelagic, one littoral and one profundal) using stable carbon and oxygen isotope values of otolith carbonate. These morphs, two of which utilized pelagic habitats, one littoral and one …
Nutrient Assimilation by First-Feeding African Catfish, Clarias gariepinus , Assessed Using Stable Isotope Analysis
Knowledge of ingredients assimilation and biomass contribution to recipient fish is important in feed formulation. The stable isotopes of 13C and 15N were used to investigate the assimilation and biomass contribution of bambaranut, Voandzeia subterranea, meal (BNM), corn, Zea mays, meal (CM) and fish meal (FM), in FM substituted diets of first feeding African catfish, Clarias gariepinus, during a 30-d experiment. The catfish larvae were stocked at 40 fish/15 L three replicate glass aquaria. Larvae were fed with experimental diets varying FM, BNM, and CM. Proportions of FM : BNM : CM in the experimental diets were: feed 1 (F1) 60:20:20; feed 2 (F2) 40:40:20; feed 3 (F3) 20:60:20; and feed 4 …
Artificial selection for predatory behavior results in dietary niche differentiation in an omnivorous mammal
AbstractThe diet of an individual is a result of the availability of dietary items and the individual’s foraging skills and preferences. Behavioral differences may thus influence diet variation, but the evolvability of diet choice through behavioral evolution has not been studied. We used experimental evolution combined with a field enclosure experiment to test whether behavioral selection leads to dietary divergence. We analysed the individual dietary niche via stable isotope ratios of nitrogen (δ15N) and carbon (δ13C) in the hair of an omnivorous mammal, bank vole, from 4 lines selected for predatory behavior and 4 unselected control lines. Predatory voles had higher hair δ15N values than…
European perch (Perca fluviatilis) fed dietary insect meal (Tenebrio molitor): From a stable isotope perspective
Abstract Stable isotope analysis was conducted to investigate stable isotope ratios of carbon (δ13C) and nitrogen (δ15N), diet-tissue discrimination factors of carbon (Δ13C) and nitrogen (Δ15Ν). Bayesian mixing models were performed to assess relative contribution of insect meal and other ingredients to the development of tissues of European perch (Perca fluviatilis). Accordingly, four experimental formulations, characterized by the increasing inclusion levels of yellow mealworm (Tenebrio molitor) larvae meal (TM) at 0, 6.8, 13.5 and 20.3% as replacement for fishmeal at 0 (TM0), 25 (TM25), 50 (TM50) and 75% (TM75), respectively, were fed to juvenile perch (initial bodyweight, 20.81 ± 3.36 g…
Influence of the marine feeding area on the muscle and egg fatty-acid composition of Atlantic salmonSalmo salarspawners estimated from the scale stable isotopes
Fatty acids in muscle tissue and eggs of female Atlantic salmon Salmo salar spawners were analysed to evaluate the dietary quality of their final feeding areas in the Baltic Sea. The final likely feeding area was identified by comparing stable carbon and nitrogen isotope composition of the outermost growth region (final annulus) of scales of returned S. salar with that of reference S. salar caught from different feeding areas. Some overlap of stable-isotope reference values among the three areas, in addition to prespawning fasting, decreased the ability of muscle tri-acylglycerols to discriminate the final likely feeding area and the area's dietary quality. Among three long-chained polyunsa…
A Bayesian stable isotope mixing model for coping with multiple isotopes, multiple trophic steps and small sample sizes
We introduce a Bayesian stable isotope mixing model for estimating the relative contributions of different dietary components to the tissues of consumers within food webs. The model is implemented with the probabilistic programming language Stan. The model incorporates isotopes of multiple elements (e.g. C, N, H) for two trophic levels, when the structure of the food web is known. In addition, the model allows inclusion of latent trophic levels (i.e. for which no empirical data are available) intermediate between sources and measured consumers. Running the model in simulations driven by a real dataset from Finnish lakes, we tested the sensitivity of the posterior distributions by altering c…
Oxygen and carbon isoscapes for the Baltic Sea : Testing their applicability in fish migration studies
Conventional tags applied to individuals have been used to investigate animal movement, but these methods require tagged individuals be recaptured. Maps of regional isotopic variability known as “isoscapes” offer potential for various applications in migration research without tagging wherein isotope values of tissues are compared to environmental isotope values. In this study, we present the spatial variability in oxygen (δ18OH2O) and dissolved inorganic carbon (δ13CDIC) isotope values of Baltic Sea water. We also provide an example of how these isoscapes can reveal locations of individual animal via spatial probability surface maps, using the high-resolution salmon otolith isotope data fr…
Stable isotopes in monitoring terrestrial arthropods
Monitoring of arthropods focuses typically on changes in population and range size over time. Yet, there are a myriad of other aspects that could and should be monitored under the ongoing global and local environmental change. Stable isotope analysis, widely employed in short-term ecological studies, has potential in long-term monitoring of arthropods. Here we discuss the use of stable isotopes in monitoring terrestrial arthropods, provide some empirical examples of the use of bulk tissue samples in stable isotope analysis, and outline future directions in using compound-specific stable isotope analysis in monitoring. We performed a literature search for 2012–2021 to see if stable isotopes …
Benthic‐pelagic coupling and trophic relationships in northern Baltic Sea food webs
Understanding marine ecosystem structure and functioning is crucial in supporting sustainable management of natural resources and monitoring the health of marine ecosystems. The current study utilized stable isotope (SI) mixing models and trophic position models to examine energy flow, trophic relationships, and benthic‐pelagic coupling between food web components. Roughly 1900 samples from different trophic levels in the food web, collected during 2001–2010 from four northern and central sub‐basins of the Baltic Sea, were analyzed for SI ratios of carbon and nitrogen. Trophic structure of the food webs among the sub‐basins was consistent, but there were differences between the proportions …
Natural recruitment contributes to high densities of grass carp Ctenopharyngodon idella (Valenciennes, 1844) in Western Europe
Introductions of grass carp, well known for their potentially negative ecosystem effects, have been performed in several countries around the world. As the species was considered unable to reproduce naturally under non-native environmental conditions, little attention was initially given to its invasive potential. We studied an area in northern-Italy where, contrary to expectations, introductions that were performed in the early 80s still exert a considerable pressure on aquatic macrophytes. In order to reveal whether the observed population dynamics are the result of natural events or stocking we analysed the density, age- and size-structure of the grass carp population and the migration p…
European catfish (Silurus glanis) as a freshwater apex predator drives ecosystem via its diet adaptability
AbstractApex predators play a key role in ecosystem stability across environments but their numbers in general are decreasing. By contrast, European catfish (Silurus glanis), the European freshwater apex predator, is on the increase. However, studies concerning apex predators in freshwaters are scarce in comparison to those in terrestrial and marine ecosystems. The present study combines stomach content and stable isotope analyses with diet preferences of catfish to reveal its impact on the ecosystem since stocking. Catfish niche width is extremely wide in comparison to the typical model predator, Northern pike (Esox lucius). Catfish and pike have different individual dietary specialization…
Short sea migration and precocious maturation in reared Atlantic salmon post-smolts in the northern Baltic Sea
Abstract Atlantic salmon (Salmo salar L.) display significant variation in life history traits, including migration patterns and age at maturity. Hatchery rearing has been shown to affect the life history, and rearing-induced changes may include unfavourable consequences, e.g. shortened sea migration period and smaller size at maturity. We report on a new phenomenon of life history of reared Atlantic salmon in the Baltic Sea area: small-sized salmon returning to freshwater only a few months after release as smolts. These “one-sea-summer (1SS)” salmon were ca. 35 cm in length and weighed ca. 400 g, being clearly larger than smolts, but substantially smaller than one-sea-winter (1SW) salmon f…
Distribution of Herbivorous Fish Is Frozen by Low Temperature.
AbstractThe number of herbivores in populations of ectothermic vertebrates decreases with increasing latitude. At higher latitudes, fish consuming plant matter are exclusively omnivorous. We assess whether omnivorous fish readily shift to herbivory or whether animal prey is typically preferred. We address temperature as the key factor causing their absence at higher latitudes and discuss the potential poleward dispersion caused by climate changes. A controlled experiment illustrates that rudd (Scardinius erythrophthalmus) readily utilize plant matter at water temperatures above 20 °C and avoid its consumption below 20 °C. Field data support these results, showing that plant matter dominates…
Migratory connectivity of two Baltic Sea salmon populations: retrospective analysis using stable isotopes of scales
Abstract Torniainen, J., Vuorinen, P. J., Jones, R. I., Keinänen, M., Palm, S., Vuori, K. A. M., and Kiljunen, M. 2014. Migratory connectivity of two Baltic Sea salmon populations: retrospective analysis using stable isotopes of scales. – ICES Journal of Marine Science, 71: 336–344. Migratory connectivity refers to the extent to which individuals of a migratory population behave in unison, and has significant consequences for the ecology, evolution and conservation of migratory animals. We made a retrospective assessment of the migratory connectivity of River Simojoki and River Kymijoki populations of Atlantic salmon Salmo salar L. by using stable isotope analysis of archived scales to iden…
Exposure to environmental radionuclides is associated with altered metabolic and immunity pathways in a wild rodent
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 with radiation exposure. To examine the effects of exposure to radiation on gene expression in wildlife, we conducted a de novo RNA sequencing study of liver and spleen tissues from a rodent, the bank vole Myodes glareolus. Bank voles were collected from the Chernobyl Exclusion Zone (CEZ), where animals were exposed to elevated levels of radionuclides, and from uncontaminated areas near Kyiv, Ukraine. Counter to expectations, we did not observe a strong DNA damage resp…
Human Dietary Intake of Organochlorines from Baltic Herring: Implications of Individual Fish Variability and Fisheries Management
This study examines the extent to which Finnish human dietary intake of organochlorines (PCDD/Fs and PCBs) originating from Northern Baltic herring can be influenced by fisheries management. This was investigated by estimation of human intake using versatile modeling tools (e.g., a herring population model and a bioenergetics model). We used a probabilistic approach to account for the variation in human intake of organochlorines originating from the variation among herring individuals. Our estimates were compared with present precautionary limits and recommendation for use. The results show that present consumption levels and frequencies of herring give a high probability of exceeding recom…
Environmentally driven changes in Baltic salmon oxidative status during marine migration.
The fitness and recruitment of fish stocks can be markedly affected by environmental disturbances including global warming, eutrophication and contamination. Understanding the effects of environmental stressors on salmon physiology during marine residence is of a global concern as marine survival has decreased. We present a unique combination of physiological responses - antioxidant defence and oxidative damage biomarkers, stable isotopes and contaminant exposure biomarkers - measured from adult Atlantic salmon (Salmo salar) collected at the Baltic Sea and studied in relation to environmental variables and fitness estimates. The results demonstrate that feeding populations of salmon display…
Macrophytes shape trophic niche variation among generalist fishes.
Generalist species commonly have a fundamental role in ecosystems as they can integrate spatially distinct habitats and food-web compartments, as well as control the composition, abundance and behavior of organisms at different trophic levels. Generalist populations typically consist of specialized individuals, but the potential for and hence degree of individual niche variation can be largely determined by habitat complexity. We compared individual niche variation within three generalist fishes between two comparable lakes in the Czech Republic differing in macrophyte cover, i.e. macrophyte-rich Milada and macrophyte-poor Most. We tested the hypothesis that large individual niche variation…
Indications of polymorphism in the behaviour and morphology of burbot (Lota lota) in a European lake
AbstractIn this study, polymorphism in behaviour, morphology, and stable isotope signatures of burbot from Lake Southern Konnevesi, Finland, Europe, was examined. First, local knowledge was collected on exceptional polymorphism of the spawning behaviour and morphology of burbot. These phenomena were then studied based on catch samples. Interviews and catch sample analyses suggested two morphs of burbot: one morph spawning in late February in the littoral zone and other in late March, in deep profundal, depths of about 30 m. Fish caught from the profundal zone had higher average proportional somatic body weights and wider heads than those caught from the littoral spawning sites in February. …
Accumulation of organochlorines in Baltic Sea fishes
Itämeri on yksi pahiten organoklooriyhdisteiden (PCB, dioksiinit, furaanit) saastuttamia merialueita. Kertyvinä ja ravintoketjuissa rikastuvina myrkkyinä ne ovat aiheuttaneet vakavia ongelmia Itämeren ravintoverkkojen huippupedoille, kuten hylkeille ja kalaa syöville petolinnuille, ja ovat myös uhka ihmisen terveydelle. Silakan myrkkypitoisuuksissa ei ole havaittu laskua 1980-luvun puolivälin jälkeen, vaikka tuntuvat päästörajoitukset ja yhdisteiden käyttökiellot ovat johtaneet taustapitoisuuksien tasaiseen laskuun Itämeressä aina 1970-luvulta saakka. Itämeren suuren silakan ja sitä syövän lohen myrkkypitoisuudet ylittävät EU:n organoklooriyhdisteille asettaman raja-arvon kaloissa ja kalatu…
Trophic transfer of polychlorinated biphenyls (PCB) in a boreal lake ecosystem: Testing of bioaccumulation models
Understanding the fate of persistent organic chemicals in the environment is fundamental information for the successful protection of ecosystems and humans. A common dilemma in risk assessment is that monitoring data reveals contaminant concentrations in wildlife, while the source concentrations, route of uptake and acceptable source concentrations remain unsolved. To overcome this problem, different models have been developed in order to obtain more precise risk estimates for the food webs. However, there is still an urgent need for studies combining modelled and measured data in order to verify the functionality of the models. Studies utilising field-collected data covering entire food we…
Stock-specific variation of trophic position, diet and environmental stress markers in Atlantic salmon Salmo salar during feeding migrations in the Baltic Sea.
This study investigated stock-specific variation in selected ecophysiological variables during the feeding migrations of Atlantic salmon Salmo salar in the Baltic Sea. Oxidative stress biomarkers and EROD (ethoxyresorufin-O-deethylase, Cyp1A enzyme) activity were used as indicators of possible environmental stress and stable isotopes as determinants of diet and trophic position. Latvian S. salar stocks Daugava and Gauja had distinct stable-isotope signatures compared to the other stocks, indicating differences in migration patterns, residency or arrival times, or dietary specialization among stocks. Salmo salar originating from Daugava and Gauja also had lower catalase enzyme activity than …
Environmental controls on benthic food web functions and carbon resource use in subarctic lakes
Climate warming and consequent greening of subarctic landscapes increase the availability of organic carbon to the detrital food webs in aquatic ecosystems. This may cause important shifts in ecosystem functioning through the functional feeding patterns of benthic organisms that rely differently on climatically altered carbon resources. Twenty-five subarctic lakes in Finnish Lapland across a tree line ecotone were analysed for limnological and optical variables, carbon (delta C-13) and nitrogen (delta N-15) stable isotope (SI) composition of surface sediment organic matter (OM) and fossil Chironomidae (Diptera) remains to examine environmental controls behind chironomid functional feeding g…
Dietary ontogeny and niche shift to piscivory in lacustrine brown trout Salmo trutta revealed by stomach content and stable isotope analyses
The feeding ecology and ontogeny of a large size range of brown trout Salmo trutta in Lake Fyresvatnet, southern Norway, were examined by stomach content and stable isotope analyses. According to the stomach contents, the S. trutta changed their diet at c. 30 cm total length (L(T) ). The smaller size classes fed on benthic invertebrates and surface insects, whereas larger S. trutta (30 cm) fed mainly on whitefish Coregonus lavaretus. A similar, but more gradual shift to piscivory in the size range 25-30 cm was found when using the stable isotope mixing model SIAR to reveal dietary ontogeny. The δ¹³C isotopic signature confirmed that S. trutta independent of size predominantly relied upon be…
A revised model for lipid-normalizing δ13C values from aquatic organisms, with implications for isotope mixing models
1. Stable isotope analyses coupled with mixing models are being used increasingly to evaluate ecological management issues and questions. Such applications of stable isotope analyses often require simultaneous carbon and nitrogen analyses from the same sample. Correction of the carbon isotope values to take account of the varying content of 13 C-depleted lipids is then frequently achieved by a lipid-normalization procedure using a model describing the relationship between change in δ 13 C following lipid removal and the original C:N ratio of a sample. 2. We evaluated the applicability of two widely used normalization models using empirical data for muscle tissue from a wide range of fish an…
Migration strategies of brown trout (Salmo trutta) in a subarctic river system as revealed by stable isotope analysis
We estimated the proportions of anadromous and freshwater‐resident brown trout (Salmo trutta) in different parts of the subarctic River Näätämöjoki/Neidenelva system (Finland and Norway) using carbon, nitrogen and hydrogen stable isotope analyses of archived scales as identifiers of migration strategy. Our results showed that carbon stable isotope values were the best predictor of migration strategy. Most individuals fell into two clearly distinct groups representing anadromous (47%) or freshwater‐resident (42%) individuals, but some fish had intermediate carbon values suggesting repeated movement between freshwater and the sea. The proportion of anadromous individuals decreased steadily wi…
Invasive crayfish increase habitat connectivity
Several studies have shown that distinct compartments of lake ecosystems are coupled via transportation of organic matter, nutrients and energy across habitat boundaries. Here we evaluate the potential of the invasive signal crayfish (Pacifastacus leniusculus (Dana)) to modify energy pathways in large boreal lakes. Using a stable isotope mixing model and calculation of the isotopic niches we estimated the contribution of different food sources to the diets of crayfish captured from different habitats, and from that inferred their potential to transport energy across the littoral-profundal gradient. The crayfish caught from the littoral area utilized mainly littoral food sources, whereas the…
Resource Partitioning in Food, Space and Time between Arctic Charr (Salvelinus alpinus), Brown Trout (Salmo trutta) and European Whitefish (Coregonus lavaretus) at the Southern Edge of Their Continuous Coexistence
Arctic charr and European whitefish are considered to be strong competitors in lakes, with the latter usually being the superior species. However, high niche plasticity and lake morphometry may suggestively facilitate resource partitioning and coexistence between charr and whitefish. Here, we explore the trophic niche utilization (diet and habitat use) of charr and whitefish co-occurring with brown trout in the deep and oligotrophic Lake Fyresvatnet, southern Norway (59˚05’N, 8˚10’E). Using CPUE, stomach contents and stable isotope analyses, a distinct resource partitioning was revealed between brown trout and the other two species. Brown trout typically occupied the littoral zone, feeding …
Artificial selection for predatory behaviour results in dietary niche differentiation in an omnivorous mammal
The diet of an individual is a result of the availability of dietary items and the individual's foraging skills and preferences. Behavioural differences may thus influence diet variation, but the evolvability of diet choice through behavioural evolution has not been studied. We used experimental evolution combined with a field enclosure experiment to test whether behavioural selection leads to dietary divergence. We analysed the individual dietary niche via stable isotope ratios of nitrogen ( δ 15 N) and carbon ( δ 13 C) in the hair of an omnivorous mammal, the bank vole, from four lines selected for predatory behaviour and four unselected control lines. Predatory voles had higher hair δ 1…
Food-web structure and mercury dynamics in a large subarctic lake following multiple species introductions
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 native communities at the food-web level, or impact energy transfer dynamics and accumulation of contaminants in lake ecosystems. Here, we explored the trophic structure of a large, oligotrophic subarctic lake and assessed the trophic niche use and potential ecosystem-wide consequences of two introduced salmonid species: piscivorous lake trout (Salvelinus namaycush) and zooplanktivorous vendace (Coregonus albula). We…
Invasive crayfish increase habitat connectivity: a case study in a large boreal lake
Several studies have shown that distinct compartments of lake ecosystems are coupled via transportation of organic matter, nutrients and energy across habitat boundaries. Here we evaluate the potential of the invasive signal crayfish (Pacifastacus leniusculus (Dana)) to modify energy pathways in large boreal lakes. Using a stable isotope mixing model and calculation of the isotopic niches we estimated the contribution of different food sources to the diets of crayfish captured from different habitats, and from that inferred their potential to transport energy across the littoral-profundal gradient. The crayfish caught from the littoral area utilized mainly littoral food sources, whereas the…
Ethanol preservation effects on stable carbon, nitrogen and hydrogen isotopes in the freshwater pearl mussel
AbstractChemical preservatives can alter stable isotope ratios in animal tissues. The effects of preservation on δ13C and δ15N values have been investigated in a variety of species, but not on δ2H values or on the freshwater pearl mussel (FPM, Margaritifera margaritifera) tissues. We evaluated the effect of ethanol preservation (unpreserved vs preserved tissues) over 6 months on the δ13C, δ15N and δ2H values of FPM foot and gonad tissues. Ethanol preservation significantly increased δ13C values (foot 0.4 ‰; gonad 0.3 ‰), whereas it did not significantly affect δ15N values (foot 0.2 ‰; gonad − 0.1 ‰). The positive effect of ethanol preservation on δ2H values (foot 7.1 ‰; gonad 14.5 ‰) and th…
Invasive catfish in northern Italy and their impacts on waterbirds
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 fish diet and the predation impacts on bird populations. We used a control/impact study setup, using a Nature Reserve in northern Italy and a nearby control area, to determine: 1) the contribution of waterbirds to wels catfish diet in the Reserve, 2) the population density of wels catfish in the Reserve and control area and 3) the potential impacts of waterbird depredation by wels catfish on waterbird population trends. Our stable isotope Bayesian mixing model indicated that birds contributed 12.2% (5–27.9%, 50% confidence inte…
Supplementary methods and results from Artificial selection for predatory behaviour results in dietary niche differentiation in an omnivorous mammal
The diet of an individual is a result of the availability of dietary items and the individual's foraging skills and preferences. Behavioural differences may thus influence diet variation, but the evolvability of diet choice through behavioural evolution has not been studied. We used experimental evolution combined with a field enclosure experiment to test whether behavioural selection leads to dietary divergence. We analysed the individual dietary niche via stable isotope ratios of nitrogen (��15N) and carbon (��13C) in the hair of an omnivorous mammal, bank vole, from four lines selected for predatory behaviour and four unselected control lines. Predatory voles had higher hair ��15N values…
Allochthony, fatty acid and mercury trends in muscle of Eurasian perch (Perca fluviatilis) along boreal environmental gradients
Environmental change, including joint effects of increasing dissolved organic carbon (DOC) and total phosphorus (TP) in boreal northern lakes could potentially affects food web energy sources and the biochemical composition of organisms. These environmental stressors are enhanced by anthropogenic land-use and can decrease the quality of polyunsaturated fatty acids (PUFAs) in seston and zooplankton, and therefore, possibly cascading up to fish. In contrast, the content of mercury in fish increases with lake browning potentially amplified by intensive forestry practises. However, there is little evidence on how these environmental stressors simultaneously impact beneficial omega-3 fatty acid …
Some like it deep : Intraspecific niche segregation in ruffe (Gymnocephalus cernua)
Generalist fishes commonly show intraspecific niche segregation along the littoral–pelagic resource axis in lakes. Recent studies have shown that the deep, cold and seemingly unproductive profundal zone can also offer underutilised resources and facilitate specialised individuals, and can contribute to lake food webs via methane-derived carbon pathways. Despite numerous examples from salmonid fish species, such intraspecific niche segregation along a littoral–profundal resource axis has not been reported in percids or other predominantly littoral benthivorous fishes. Here, we describe a case of ruffe (Gymnocephalus cernua: Percidae) populations consisting of shallow- and deep-water dwelling…
Biomagnification of organohalogens in Atlantic salmon (Salmo salar) from its main prey species in three areas of the Baltic Sea
Abstract Factors affecting the biomagnification of organohalogens in Baltic salmon from sprat, herring and three-spined stickleback were assessed in three feeding areas. Second sea-year salmon contained (in fresh weight of whole fish) 79–250 ng g− 1 polychlorinated biphenyls (ΣPCB), 0.9–2.7 pg g− 1 dibenzo-p-dioxins (ΣPCDD), 8–19 pg g− 1 dibenzofurans (ΣPCDF), 96–246 pg g− 1 coplanar PCBs, 2.4–3.6 ng g− 1 polybrominated diphenylethers (ΣPBDE), and 39–136 ng g− 1 Σindicator PCB6. The EU limits for WHO toxic equivalent concentrations in fish feed were already exceeded in one-year-old sprat and herring and were exceeded many-fold in older age groups. The differences in the biomagnification rat…
Feeding Aquatic Ecosystems : Whole-Lake Experimental Addition of Angler’s Ground Bait Strongly Affects Omnivorous Fish Despite Low Contribution to Lake Carbon Budget
It is well documented that aquatic ecosystems may be subsidized by naturally derived terrestrial carbon sources. In contrast, the intentional or unintentional subsidy of animal populations by human-derived feed resources and their ecosystem effects are poorly studied. We added ground baits of the type, amount and temporal duration commonly applied by anglers targeting cyprinid fishes to a small lake, and studied behavior, diet composition and annual growth rate of the lake fish community in response to the bait addition. Based on recordings by a high-resolution ultrasonic telemetry array, common carp (Cyprinus carpio) as a model benthivore spend more time at the sites where ground baits wer…
Supplementary material 1 from: Milardi M, Green AJ, Mancini M, Trotti P, Kiljunen M, Torniainen J, Castaldelli G (2022) Invasive catfish in northern Italy and their impacts on waterbirds. NeoBiota 72: 109-128. https://doi.org/10.3897/neobiota.72.80500
Figures and Tables
Data from: Oxygen and carbon isoscapes for the Baltic Sea: testing their applicability in fish migration studies
Conventional tags applied to individuals have been used to investigate animal movement, but these methods require tagged individuals be recaptured. Maps of regional isotopic variability known as “isoscapes” offer potential for various applications in migration research without tagging wherein isotope values of tissues are compared to environmental isotope values. In this study, we present the spatial variability in oxygen (math formula) and dissolved inorganic carbon (δ13CDIC) isotope values of Baltic Sea water. We also provide an example of how these isoscapes can reveal locations of individual animal via spatial probability surface maps, using the high-resolution salmon otolith isotope da…
Lisämateriaali artikkeliin "Exposure to environmental radionuclides is associated with altered metabolic and immunity pathways in a wild rodent".
Electronic material for Kesäniemi J, Jernfors T, Lavrinienko A, Kivisaari K, Kiljunen M, Mappes T & Watts PC. 2019. Exposure to environmental radionuclides is associated with altered metabolic and immunity pathways in a wild rodent. Molecular Ecology 28: 4620–4635. Contains transcriptome annotation data and output of differential expression and gene ontology enrichment analyses. Parts of the dataset originally published in DRYAD (https://doi.org/10.5061/dryad.j3c6r69).