0000000001300029
AUTHOR
Silva Uusi-heikkilä
Genetic-based evaluation of management units for sustainable vendace (Coregonus albula) fisheries in a large lake system
Abstract The goal of the processing industry, trade and consumers is to get eco-labelled freshwater fish products from sustainable fisheries into the market as soon as possible. The fourth largest natural lake system in Europe, the Saimaa lake system supports a fishery for vendace (Coregonus albula). Certification of the fishery requires an understanding of population structure to help determine the number and spatial extent of management units. In this study, we analysed the genetic diversity of local vendace populations in the Saimaa lake system and aimed to identify the conservation and management units of vendace. Within the Saimaa, the genetic divergence between local populations of ve…
Genome-wide divergence patterns support fine-scaled genetic structuring associated with migration tendency in brown trout
Brown trout (Salmo trutta) exhibit highly diverse life histories varying from resident, slow-growing, and early maturing to migratory, fast-growing, and late maturing, even within single watersheds. We sampled 11 locations within the transboundary Finnish–Russian River Koutajoki watershed to evaluate genomic differences among mainstem and headwater sites, of which some are isolated by migration barriers. Restriction site associated sequencing (RADSeq) revealed that the most headwater localities supported unique, isolated populations with generally lower heterozygosity compared with the mainstem populations. The sampled migratory adults in the three main stems showed signals of admixture de…
Correction: Size does matter—the eco-evolutionary effects of changing body size in fish
Comparing RADseq and microsatellites for estimating genetic diversity and relatedness : Implications for brown trout conservation
The conservation and management of endangered species requires information on their genetic diversity, relatedness and population structure. The main genetic markers applied for these questions are microsatellites and single nucleotide polymorphisms (SNPs), the latter of which remain the more resource demanding approach in most cases. Here, we compare the performance of two approaches, SNPs obtained by restriction-site-associated DNA sequencing (RADseq) and 16 DNA microsatellite loci, for estimating genetic diversity, relatedness and genetic differentiation of three, small, geographically close wild brown trout (Salmo trutta) populations and a regionally used hatchery strain. The genetic di…
Size does matter — the eco-evolutionary effects of changing body size in fish
Body size acts as a proxy for many fitness-related traits. Body size is also subject to directional selection from various anthropogenic stressors such as increasing water temperature, decreasing dissolved oxygen, fisheries, as well as natural predators. Changes in individual body size correlate with changes in fecundity, behaviour, and survival and can propagate through populations and ecosystems by truncating age and size structures and changing predator–prey dynamics. In this review, we will explore the causes and consequences of changing body size in fish in the light of recent literature and relevant theories. We will investigate the central role of body size in ecology by first discu…
Species’ ecological functionality alters the outcome of fish stocking success predicted by a food-web model
Fish stocking is used worldwide in conservation and management, but its effects on food-web dynamics and ecosystem stability are poorly known. To better understand these effects and predict the outcomes of stocking, we used an empirically validated network model of a well-studied lake ecosystem. We simulate two stocking scenarios with two native fish species valuable for fishing. In the first scenario, we stock planktivorous fish (whitefish) larvae in the ecosystem. This leads to a 1% increase in adult whitefish biomasses and decreases the biomasses of the top predator (perch). In the second scenario, we also stock perch larvae in the ecosystem. This decreases the planktivorous whitefish an…
Figure S4 from Species' ecological functionality alters the outcome of fish stocking success predicted by a food-web model
Changes in the adult whitefish and perch biomasses in response to increased whitefish (Wht300; black) and perch stocking (Wht300+Per50; red) compared to the whitefish baseline (Wht200; gray) under Fmax = 0.4 (10% lower fishing pressure than in the main text), Fmax = 0.5 (fishing pressure in the main text), and under Fmax = 0.6 (10% higher fishing pressure than in the main text). Dashed lines indicate the time point when fishing was introduced to the simulations.
Figure S1 from Species' ecological functionality alters the outcome of fish stocking success predicted by a food-web model
Changes in the adult whitefish and perch catches (as biomass densities) in response to increased whitefish (Wht300; black) and perch stocking (Wht300+Per50; red) compared to the whitefish baseline (Wht200; gray) during the 100 year fishing period.
Are there plenty of fish in the sea? How life history traits affect the eco-evolutionary consequences of population oscillations
Understanding fish population oscillations is important for both fundamental population biology and for fisheries science. Much research has focused on the causes of population oscillations, but the eco-evolutionary consequences of population oscillations are unclear. Here, we used an empirically parametrised individual-based simulation model to explore the consequences of oscillations with different amplitudes and wavelengths. We show that oscillations with a wavelength shorter than the maximum lifespan of the fish produce marked differences in the evolutionary trajectories of asymptotic length. Wavelengths longer than the maximum lifespan of the fish, in turn, mainly manifest as ecologica…
Implications of size‐selective fisheries on sexual selection
Fisheries often combine high mortality with intensive size‐selectivity and can, thus, be expected to reduce body size and size variability in exploited populations. In many fish species, body size is a sexually selected trait and plays an important role in mate choice and mate competition. Large individuals are often preferred as mates due to the high fecundity and resources they can provide to developing offspring. Large fish are also successful in competition for mates. Fisheries‐induced reductions in size and size variability can potentially disrupt mating systems and lower average reproductive success by decreasing opportunities for sexual selection. By reducing population sizes, fisher…
ESM - Material and Methods from Species' ecological functionality alters the outcome of fish stocking success predicted by a food-web model
Fish stocking is used worldwide in conservation and management, but its effects on food-web dynamics and ecosystem stability are poorly known. To better understand these effects and predict the outcomes of stocking, we used an empirically validated network model of a well-studied lake ecosystem. We simulate two stocking scenarios with two native fish species valuable for fishing. In the first scenario, we stock planktivorous fish (whitefish) larvae in the ecosystem. This leads to a 1% increase in adult whitefish biomasses and decreases the biomasses of the top predator (perch). In the second scenario, we also stock perch larvae in the ecosystem. This decreases the planktivorous whitefish an…
Return of the Apex Predator : How Brown Trout (Salmo trutta) Re-Establishment Shapes an Ecosystem
Re-establishment of a declined apex predator fish species in a lake ecosystem may have dramatic effects on other fish and plankton community already inhabiting the ecosystem. We studied mechanistically potential impacts of re-establishment of the brown trout (Salmo trutta) in the west-central European Lake Constance focusing on two commercially important fish species: whitefish and Eurasian perch. We compared simulation model outputs from two versions of an allometric trophic network model for Lake Constance, one with and one without the trout as the apex predator. The re-establishment of the declined brown trout reduced the perch population directly by predation and indirectly by increased…
Association Mapping Based on a Common-Garden Migration Experiment Reveals Candidate Genes for Migration Tendency in Brown Trout
A better understanding of the environmental and genetic contribution to migratory behavior and the evolution of traits linked to migration is crucial for fish conservation and fisheries management. Up to date, a few genes with unequivocal influence on the adoption of alternative migration strategies have been identified in salmonids. Here, we used a common garden set-up to measure individual migration distances of generally highly polymorphic brown trout Salmo trutta from two populations. Fish from the assumedly resident population showed clearly shorter migration distances than the fish from the assumed migratory population at the ages of 2 and 3 years. By using two alternative analytical …
Figure S4 from Species' ecological functionality alters the outcome of fish stocking success predicted by a food-web model
Changes in the adult whitefish and perch biomasses in response to increased whitefish (Wht300; black) and perch stocking (Wht300+Per50; red) compared to the whitefish baseline (Wht200; gray) under Fmax = 0.4 (10% lower fishing pressure than in the main text), Fmax = 0.5 (fishing pressure in the main text), and under Fmax = 0.6 (10% higher fishing pressure than in the main text). Dashed lines indicate the time point when fishing was introduced to the simulations.
Figure S3 from Species' ecological functionality alters the outcome of fish stocking success predicted by a food-web model
Changes in the adult perch biomasses in response to perch stocking (Wht300+Per50 [red]; Wht300+Per25 [pink]; Wht300+Per75 [orange]) compared to the increased whitefish stocking (Wht300 [black]). Dashed lines indicate the time point when fishing was introduced to the simulations.
Figure S1 from Species' ecological functionality alters the outcome of fish stocking success predicted by a food-web model
Changes in the adult whitefish and perch catches (as biomass densities) in response to increased whitefish (Wht300; black) and perch stocking (Wht300+Per50; red) compared to the whitefish baseline (Wht200; gray) during the 100 year fishing period.
Figure S2 from Species' ecological functionality alters the outcome of fish stocking success predicted by a food-web model
Changes in the adult whitefish biomasses in response to increased whitefish stocking (Wht250 [light blue]; Wht300 [black]; Wht350 [dark blue]) compared to the whitefish baseline (Wht200 [light gray]). Dashed lines indicate the time point when fishing was introduced to the simulations.
Experimental size-selective harvesting affects behavioral types of a social fish
In most fisheries, larger fish experience substantially higher mortality than smaller fish. Body length, life history, and behavioral traits are often correlated, such that fisheries-induced changes in size or life history can also alter behavioral traits. However, empirical evidence regarding how size-selective harvesting alters the evolution of behavioral traits in exploited stocks is scarce. We used experimental lines of Zebrafish Danio rerio that were exposed to positively size-selective, negatively size-selective, or random harvest over five generations. Our aim was to investigate whether simulated fishing changed the mean personality of the surviving females five generations after ini…
Size‐selective harvesting fosters adaptations in mating behaviour and reproductive allocation, affecting sexual selection in fish
The role of sexual selection in the context of harvest-induced evolution is poorly understood. However, elevated and trait-selective harvesting of wild populations may change sexually selected traits, which in turn can affect mate choice and reproduction. We experimentally evaluated the potential for fisheries-induced evolution of mating behaviour and reproductive allocation in fish. We used an experimental system of zebrafish (Danio rerio) lines exposed to large, small or random (i.e. control) size-selective mortality. The large-harvested line represented a treatment simulating the typical case in fisheries where the largest individuals are preferentially harvested. We used a full factoria…
Figure S2 from Species' ecological functionality alters the outcome of fish stocking success predicted by a food-web model
Changes in the adult whitefish biomasses in response to increased whitefish stocking (Wht250 [light blue]; Wht300 [black]; Wht350 [dark blue]) compared to the whitefish baseline (Wht200 [light gray]). Dashed lines indicate the time point when fishing was introduced to the simulations.
Comparison of migratory and resident populations of brown trout reveals candidate genes for migration tendency
Candidate genes associated with migration have been identified in multiple taxa: including salmonids, many of whom perform migrations requiring a series of physiological changes associated with the freshwater–saltwater transition. We screened over 5,500 SNPs for signatures of selection related to migratory behavior of brown trout Salmo trutta by focusing on ten differentially migrating freshwater populations from two watersheds (the Koutajoki and the Oulujoki). We found eight outlier SNPs potentially associated with migratory versus resident life history using multiple (≥3) outlier detection approaches. Comparison of three migratory versus resident population pairs in the Koutajoki watershe…
Size-selective harvesting fosters adaptations in mating behavior and reproductive allocation, affecting sexual selection in fish
The role of sexual selection in the context of harvest‐induced evolution is poorly understood. However, elevated and trait‐selective harvesting of wild populations may change sexually selected traits, which in turn can affect mate choice and reproduction. We experimentally evaluated the potential for fisheries‐induced evolution of mating behaviour and reproductive allocation in fish. We used an experimental system of zebrafish (Danio rerio) lines exposed to large, small or random (i.e. control) size‐selective mortality. The large‐harvested line represented a treatment simulating the typical case in fisheries where the largest individuals are preferentially harvested. We used a full factoria…
Fishing triggers trophic cascade in terms of variation, not abundance, in an allometric trophic network model
Trophic cascade studies often rely on linear food chains instead of complex food webs and are typically measured as biomass averages, not as biomass variation. We study trophic cascades propagating across a complex food web including a measure of biomass variation in addition to biomass average. We examined whether different fishing strategies induce trophic cascades and whether the cascades differ from each other. We utilized an allometric trophic network (ATN) model to mechanistically study fishing-induced changes in food web dynamics. Different fishing strategies did not trigger traditional, reciprocal trophic cascades, as measured in biomass averages. Instead, fishing triggered a varia…
Age is not just a number—Mathematical model suggests senescence affects how fish populations respond to different fishing regimes
Abstract Senescence is often described as an age‐dependent increase in natural mortality (known as actuarial senescence) and an age‐dependent decrease in fecundity (known as reproductive senescence), and its role in nature is still poorly understood. Based on empirical estimates of reproductive and actuarial senescence, we used mathematical simulations to explore how senescence affects the population dynamics of Coregonus albula, a small, schooling salmonid fish. Using an empirically based eco‐evolutionary model, we investigated how the presence or absence of senescence affects the eco‐evolutionary dynamics of a fish population during pristine, intensive harvest, and recovery phases. Our si…
Comparison of Migratory and Resident Populations of Brown Trout Reveals Candidate Genes for Migration Tendency
Abstract Candidate genes associated with migration have been identified in multiple taxa: including salmonids, many of whom perform migrations requiring a series of physiological changes associated with the freshwater–saltwater transition. We screened over 5,500 SNPs for signatures of selection related to migratory behavior of brown trout Salmo trutta by focusing on ten differentially migrating freshwater populations from two watersheds (the Koutajoki and the Oulujoki). We found eight outlier SNPs potentially associated with migratory versus resident life history using multiple (≥3) outlier detection approaches. Comparison of three migratory versus resident population pairs in the Koutajoki…
ESM - Material and Methods from Species' ecological functionality alters the outcome of fish stocking success predicted by a food-web model
Fish stocking is used worldwide in conservation and management, but its effects on food-web dynamics and ecosystem stability are poorly known. To better understand these effects and predict the outcomes of stocking, we used an empirically validated network model of a well-studied lake ecosystem. We simulate two stocking scenarios with two native fish species valuable for fishing. In the first scenario, we stock planktivorous fish (whitefish) larvae in the ecosystem. This leads to a 1% increase in adult whitefish biomasses and decreases the biomasses of the top predator (perch). In the second scenario, we also stock perch larvae in the ecosystem. This decreases the planktivorous whitefish an…
Figure S3 from Species' ecological functionality alters the outcome of fish stocking success predicted by a food-web model
Changes in the adult perch biomasses in response to perch stocking (Wht300+Per50 [red]; Wht300+Per25 [pink]; Wht300+Per75 [orange]) compared to the increased whitefish stocking (Wht300 [black]). Dashed lines indicate the time point when fishing was introduced to the simulations.
Chemical composition and particle size influence the toxicity of nanoscale plastic debris and their co-occurring benzo(α)pyrene in the model aquatic organisms Daphnia magna and Danio rerio
Little is known about how particle chemical composition and size might influence the toxicity of nanoscale plastic debris (NPD) and their co-occurring chemicals. Herein, we investigate the toxicity of 3 × 1010 particles/L polyethylene (PE, 50 nm), polypropylene (PP, 50 nm), polystyrene (PS, 200 and 600 nm), and polyvinyl chloride (PVC, 200 nm) NPD and their co-occurring benzo(a)pyrene (BaP) to Daphnia magna and Danio rerio. During the 21 days of exposure to PE 50 nm and PS 200 nm, the number of broods produced by D. magna decreased compared to other treatments. Exposure to BaP alone did not produce any effects on the reproduction of the daphnids, however, the mixture of BaP with PS (200 or …
Age is not just a number – senescence affects how fish populations respond to different fishing regimes
Abstract The presence of senescence in natural populations remains an unsolved problem in biology. Described as an age-dependent increase in natural mortality (known as actuarial senescence) and an age-dependent decrease in fecundity (known as reproductive senescence), the role of senescence in nature is still poorly understood. Based on empirical estimates of reproductive and actuarial senescence, we explored how senescence affects the population dynamics of Coregonus albula, a small, schooling salmonid fish. Using an empirically-based eco-evolutionary model, we investigated how the presence or absence of senescence affects how the fish population responds to pristine, intensive harvest, a…
Sustainability of Fishing Is about Abundance: A Response to Bernatchez et al.
Overfishing together with uncertainty or lack of recovery are characteristic challenges to fisheries management [1]. To realistically account for the multiple drivers of fish population abundances, ecosystem-based fisheries management has been accepted as the future avenue to assess and manage fisheries. However, practical implementations of ecosystem-based fisheries management remain rare, largely because of the lack of methodology and skills [2]. The discrepancy between the aims to conduct ecosystem-based and scientifically sound fisheries management and the prevailing practices becomes even wider when contrasting developed and developing countries [3].
Genetic-based evaluation of management units for sustainable vendace (Coregonus albula) fisheries in a large lake system
The goal of the processing industry, trade and consumers is to get eco-labelled freshwater fish products from sustainable fisheries into the market as soon as possible. The fourth largest natural lake system in Europe, the Saimaa lake system supports a fishery for vendace (Coregonus albula). Certification of the fishery requires an understanding of population structure to help determine the number and spatial extent of management units. In this study, we analysed the genetic diversity of local vendace populations in the Saimaa lake system and aimed to identify the conservation and management units of vendace. Within the Saimaa, the genetic divergence between local populations of vendace was…
Data from: Size-selective harvesting fosters adaptations in mating behavior and reproductive allocation, affecting sexual selection in fish
1. The role of sexual selection in the context of harvest-induced evolution is poorly understood. However, elevated and trait-selective harvesting of wild populations may change sexually-selected traits, which in turn can affect mate choice and reproduction. 2. We experimentally evaluated the potential for fisheries-induced evolution of mating behavior and reproductive allocation in fish. 3. We used a unique experimental system of zebrafish (Danio rerio) lines exposed to large, small, or random (i.e. control) size-selective mortality. The large-harvested line represented a treatment simulating the typical case in fisheries where the largest individuals are preferentially harvested. We used …
Data from: Species’ ecological functionality alters the outcome of fish stocking success predicted by a food-web model
Fish stocking is used worldwide in conservation and management but its effects on food-web dynamics and ecosystem stability are poorly known. To better understand these effects and predict the outcomes of stocking, we used an empirically validated network model of a well-studied lake ecosystem. We simulate two stocking scenarios with two native fish species valuable for fishing. In the first scenario, we stock planktivorous fish (whitefish) larvae in the ecosystem. This leads to 1% increase in adult whitefish biomasses and decreases the biomasses of the top predator (perch). In the second scenario, we also stock perch larvae in the ecosystem. This decreases the planktivorous whitefish and t…
Supplemental Material for Lemopoulos et al., 2019
Beagle file for the ANGSD pipeline. Genotype probabilities of 116 brown trout. 7520 SNPs are identified and mapped to corresponding location in the Atlantic salmon genome.
Management of human-induced contemporary evolution to maintain and restore genetic diversity in brown trout
Maintaining genetic diversity and integrity of animal populations is a key challenge in conservation. While ecological population declines can be reversed, loss of genetic diversity and original trait distribution is often a one-way road. Migratory brown trout is critically endangered in Finland due to extensive modification of river ecosystems and unrestricted fishing on feeding areas. In addition to being too intense in general, fishing creates challenges by being selective for a number of traits in fish. We have shown that recreational angling, for example, is selective for certain personality traits and can cause inherited behavioural changes in the offspring of brown trout. Only a few …
Genetic causes and consequences of Brown trout migratory behaviour
Salmonids are among the most famous and economically important migrating organisms, but unfortunately also often endangered because of multiple human activities. As many other salmonids, brown trout exhibits diverse life history types related to migration strategies. Resident brown trout stay in rivers for their entire life. In contrast, migratory trout undergo a physiological and morphological transformation called smoltification before leaving their natal rivers to enter either sea, lakes or larger river sections. While the phenotypic variation between resident and migratory ecotypes is well documented, little is known about the intraspecific genetic variation associated with these differ…