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We explored the implications of reaching the Paris Agreement Objective of limiting global warming to <2°C for the future winter distribution of the North Atlantic seabird community. We predicted and quantified current and future winter habitats of five North Atlantic Ocean seabird species (Alle alle, Fratercula arctica, Uria aalge, Uria lomvia and Rissa tridactyla) using tracking data for ~1500 individuals through resource selection functions based on mechanistic modeling of seabird energy requirements, and a dynamic bioclimate envelope model of seabird prey. Future winter distributions were predicted to shift with climate change, especially when global warming exceed 2°C under a "no mitigation" scenario, modifying seabird wintering hotspots in the North Atlantic Ocean. Our findings suggest that meeting Paris agreement objectives will limit changes in seabird selected habitat location and size in the North Atlantic Ocean during the 21st century. We thereby provide key information for the design of adaptive marine-protected areas in a changing ocean.
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Mudança Climática , Ecossistema , Animais , Oceano Atlântico , Humanos , Paris , Estações do AnoRESUMO
The increased comparative research on perceptions of public welfare deservingness studies the extent to which different subgroups of citizens are deemed worthy or unworthy of receiving help from the welfare state. The concept of deservingness criteria plays a crucial role in this research, as it theorizes a universal heuristic that citizens apply to rank people in terms of their welfare deservingness. Due to the mainly quantitative nature of the research and despite the indisputable progress it has made, the subjective existence and actual application of these deservingness criteria remain a bit of a black box. What criteria of deservingness do citizens actually apply, and how do they apply them? This article opens the black box of welfare deservingness and sheds light on the nature and practice of deservingness criteria. Empirically, the paper explores how the deservingness of immigrants is discussed and established within 20 focus groups conducted in Slovenia, Denmark, UK, and Norway in 2016 with a total of 160 participants. All 20 focus groups discussed the welfare deservingness of immigrants based on similar vignette stimuli. Our analysis shows that (1) deservingness criteria are used both to construct images of target groups and as normative yardsticks; (2) deservingness criteria do not work independently of each other, but rather co-function in specific hybridized discourses; and (3) the moral logic of deservingness is supplemented by alternative moral logics, at least in the case of migrants.
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Emigrantes e Imigrantes , Seguridade Social , Migrantes , Adulto , Idoso , Atitude , Dinamarca , Emigrantes e Imigrantes/psicologia , Feminino , Grupos Focais , Heurística , Humanos , Masculino , Pessoa de Meia-Idade , Princípios Morais , Noruega , Eslovênia , Seguridade Social/ética , Migrantes/psicologia , Reino UnidoRESUMO
The duration of parental care in animals varies widely, from none to lifelong. Such variation is typically thought to represent a trade-off between growth and safety. Seabirds show wide variation in the age at which offspring leave the nest, making them ideal to test the idea that a trade-off between high energy gain at sea and high safety at the nest drives variation in departure age (Ydenberg's model). To directly test the model assumptions, we attached time-depth recorders to murre parents (fathers [which do all parental care at sea] and mothers; [Formula: see text] of each). Except for the initial mortality experienced by chicks departing from the colony, the mortality rate at sea was similar to the mortality rate at the colony. However, energy gained by the chick per day was â¼2.1 times as high at sea compared with at the colony because the father spent more time foraging, since he no longer needed to spend time commuting to and from the colony. Compared with the mother, the father spent â¼2.6 times as much time diving per day and dived in lower-quality foraging patches. We provide a simple model for optimal departure date based on only (1) the difference in growth rate at sea relative to the colony and (2) the assumption that transition mortality from one life-history stage to the other is size dependent. Apparently, large variation in the duration of parental care can arise simply as a result of variation in energy gain without any trade-off with safety.
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Charadriiformes/fisiologia , Ingestão de Energia , Comportamento Alimentar , Longevidade , Modelos Biológicos , Animais , Charadriiformes/crescimento & desenvolvimento , Mergulho , Ecossistema , Feminino , Masculino , PaisRESUMO
Climate change alters species distributions by shifting their fundamental niche in space through time. Such effects may be exacerbated by increased inter-specific competition if climate alters species dominance where competitor ranges overlap. This study used census data, telemetry and stable isotopes to examine the population and foraging ecology of a pair of Arctic and temperate congeners across an extensive zone of sympatry in Iceland, where sea temperatures varied substantially. The abundance of Arctic Brünnich's guillemot Uria lomvia declined with sea temperature. Accessibility of refugia in cold water currents or fjords helped support higher numbers and reduce rates of population decline. Competition with temperate Common guillemots Uria aalge did not affect abundance, but similarities in foraging ecology were sufficient to cause competition when resources are limiting. Continued warming is likely to lead to further declines of Brünnich's guillemot, with implications for conservation status and ecosystem services.
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Charadriiformes , Mudança Climática , Animais , Regiões Árticas , Ecossistema , Estuários , Gelo , Camada de Gelo , Refúgio de Vida SelvagemRESUMO
Oral administration provides a simple and non-invasive approach for drug delivery. However, due to poor absorption and swift enzymatic degradation in the gastrointestinal tract, a wide range of molecules must be parenterally injected to attain required doses and pharmacokinetics. Here we present an orally dosed liquid auto-injector capable of delivering up to 4-mg doses of a bioavailable drug with the rapid pharmacokinetics of an injection, reaching an absolute bioavailability of up to 80% and a maximum plasma drug concentration within 30 min after dosing. This approach improves dosing efficiencies and pharmacokinetics an order of magnitude over our previously designed injector capsules and up to two orders of magnitude over clinically available and preclinical chemical permeation enhancement technologies. We administered the capsules to swine for delivery of clinically relevant doses of four commonly injected medications, including adalimumab, a GLP-1 analog, recombinant human insulin and epinephrine. These multi-day dosing experiments and oral administration in awake animal models support the translational potential of the system.
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Anticorpos Monoclonais , Antineoplásicos Imunológicos , Administração Oral , Animais , Disponibilidade Biológica , Cápsulas , Imunoterapia , Peptídeos , SuínosRESUMO
Density-dependent prey depletion around breeding colonies has long been considered an important factor controlling the population dynamics of colonial animals.1-4 Ashmole proposed that as seabird colony size increases, intraspecific competition leads to declines in reproductive success, as breeding adults must spend more time and energy to find prey farther from the colony.1 Seabird colony size often varies over several orders of magnitude within the same species and can include millions of individuals per colony.5,6 As such, colony size likely plays an important role in determining the individual behavior of its members and how the colony interacts with the surrounding environment.6 Using tracking data from murres (Uria spp.), the world's most densely breeding seabirds, we show that the distribution of foraging-trip distances scales to colony size0.33 during the chick-rearing stage, consistent with Ashmole's halo theory.1,2 This pattern occurred across colonies varying in size over three orders of magnitude and distributed throughout the North Atlantic region. The strong relationship between colony size and foraging range means that the foraging areas of some colonial species can be estimated from colony sizes, which is more practical to measure over a large geographic scale. Two-thirds of the North Atlantic murre population breed at the 16 largest colonies; by extrapolating the predicted foraging ranges to sites without tracking data, we show that only two of these large colonies have significant coverage as marine protected areas. Our results are an important example of how theoretical models, in this case, Ashmole's version of central-place-foraging theory, can be applied to inform conservation and management in colonial breeding species.
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Charadriiformes , Animais , Ecossistema , Dinâmica Populacional , ReproduçãoRESUMO
The rapidly changing climate in the Arctic is expected to have a major impact on the foraging ecology of seabirds, owing to changes in the distribution and abundance of their prey but also that of competitors (e.g. southerly species expanding their range into the Arctic). Species can respond to interspecific competition by segregating along different niche axes. Here, we studied spatial, temporal and habitat segregation between two closely related seabird species: common guillemot Uria aalge (a temperate species) and Brünnich's guillemot Uria lomvia (a true Arctic species), at two sympatric sites in Iceland that differ in their total population sizes and the availability of marine habitats. We deployed GPS and temperature-depth recorders to describe foraging locations and behaviour of incubating and chick-rearing adults. We found similar evidence of spatial segregation at the two sites (i.e. independent of population sizes), although segregation in environmental space was only evident at the site with a strong habitat gradient. Unexpectedly, temporal (and, to a limited extent, vertical) segregation appeared only at the least populated site. Overall, our results show complex relationships between the levels of inferred competition and that of segregation.
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Alternative means for drug delivery are needed to facilitate drug adherence and administration. Microneedles (MNs) have been previously investigated transdermally for drug delivery. To date, drug loading into MNs has been limited by drug solubility in the polymeric blend. We designed a highly drug-loaded MN patch to deliver macromolecules and applied it to the buccal area, which allows for faster delivery than the skin. We successfully delivered 1-mg payloads of human insulin and human growth hormone to the buccal cavity of swine within 30 s. In addition, we conducted a trial in 100 healthy volunteers to assess potential discomfort associated with MNs when applied in the oral cavity, identifying the hard palate as the preferred application site. We envisage that MN patches applied on buccal surfaces could increase medication adherence and facilitate the painless delivery of biologics and other drugs to many, especially for the pediatric and elderly populations.
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Each winter, the North Atlantic Ocean is the stage for numerous cyclones, the most severe ones leading to seabird mass-mortality events called "winter wrecks."1-3 During these, thousands of emaciated seabird carcasses are washed ashore along European and North American coasts. Winter cyclones can therefore shape seabird population dynamics4,5 by affecting survival rates as well as the body condition of surviving individuals and thus their future reproduction. However, most often the geographic origins of impacted seabirds and the causes of their deaths remain unclear.6 We performed the first ocean-basin scale assessment of cyclone exposure in a seabird community by coupling winter tracking data for â¼1,500 individuals of five key North Atlantic seabird species (Alle alle, Fratercula arctica, Uria aalge, Uria lomvia, and Rissa tridactyla) and cyclone locations. We then explored the energetic consequences of different cyclonic conditions using a mechanistic bioenergetics model7 and tested the hypothesis that cyclones dramatically increase seabird energy requirements. We demonstrated that cyclones of high intensity impacted birds from all studied species and breeding colonies during winter but especially those aggregating in the Labrador Sea, the Davis Strait, the surroundings of Iceland, and the Barents Sea. Our broad-scale analyses suggested that cyclonic conditions do not increase seabird energy requirements, implying that they die because of the unavailability of their prey and/or their inability to feed during cyclones. Our study provides essential information on seabird cyclone exposure in a context of marked cyclone regime changes due to global warming.8.
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Charadriiformes , Tempestades Ciclônicas , Animais , Oceano Atlântico , Aves , Humanos , Estações do AnoRESUMO
Ingestible electronic devices enable noninvasive evaluation and diagnosis of pathologies in the gastrointestinal (GI) tract but generally cannot therapeutically interact with the tissue wall. Here, we report the development of an orally administered electrical stimulation device characterized in ex vivo human tissue and in in vivo swine models, which transiently anchored itself to the stomach by autonomously inserting electrically conductive, hooked probes. The probes provided stimulation to the tissue via timed electrical pulses that could be used as a treatment for gastric motility disorders. To demonstrate interaction with stomach muscle tissue, we used the electrical stimulation to induce acute muscular contractions. Pulses conductively signaled the probes' successful anchoring and detachment events to a parenterally placed device. The ability to anchor into and electrically interact with targeted GI tissues controlled by the enteric nervous system introduces opportunities to treat a multitude of associated pathologies.
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Alternatives in ecosystem-based management often differ with respect to trade-offs between ecosystem values. Ecosystem or food-web models and demographic models are typically employed to evaluate alternatives, but the approaches are rarely integrated to uncover conflicts between values. We applied multistate models to a capture-recapture dataset on common guillemots Uria aalge breeding in the Baltic Sea to identify factors influencing survival. The estimated relationships were employed together with Ecopath-with-Ecosim food-web model simulations to project guillemot survival under six future scenarios incorporating climate change. The scenarios were based on management alternatives for eutrophication and cod fisheries, issues considered top priority for regional management, but without known direct effects on the guillemot population. Our demographic models identified prey quantity (abundance and biomass of sprat Sprattus sprattus) as the main factor influencing guillemot survival. Most scenarios resulted in projections of increased survival, in the near (2016-2040) and distant (2060-2085) future. However, in the scenario of reduced nutrient input and precautionary cod fishing, guillemot survival was projected to be lower in both future periods due to lower sprat stocks. Matrix population models suggested a substantial decline of the guillemot population in the near future, 24% per 10 years, and a smaller reduction, 1.1% per 10 years, in the distant future. To date, many stakeholders and Baltic Sea governments have supported reduced nutrient input and precautionary cod fishing and implementation is underway. Negative effects on nonfocal species have previously not been uncovered, but our results show that the scenario is likely to negatively impact the guillemot population. Linking model results allowed identifying trade-offs associated with management alternatives. This information is critical to thorough evaluation by decision-makers, but not easily obtained by food-web models or demographic models in isolation. Appropriate datasets are often available, making it feasible to apply a linked approach for better-informed decisions in ecosystem-based management.
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Harvested species population dynamics are shaped by the relative contribution of natural and harvest mortality. Natural mortality is usually not under management control, so managers must continuously adjust harvest rates to prevent overexploitation. Ideally, this requires regular assessment of the contribution of harvest to total mortality and how this affects population dynamics.To assess the impact of hunting mortality on the dynamics of the rapidly declining Baltic/Wadden Sea population of common eiders Somateria mollissima, we first estimated vital rates of ten study colonies over the period 1970-2015. By means of a multi-event capture-recovery model, we then used the cause of death of recovered individuals to estimate proportions of adult females that died due to hunting or other causes. Finally, we adopted a stochastic matrix population modeling approach based on simulations to investigate the effect of past and present harvest regulations on changes in flyway population size and composition.Results showed that even the complete ban on shooting females implemented in 2014 in Denmark, where most hunting takes place, was not enough to stop the population decline given current levels of natural female mortality. Despite continued hunting of males, our predictions suggest that the proportion of females will continue to decline unless natural mortality of the females is reduced.Although levels of natural mortality must decrease to halt the decline of this population, we advocate that the current hunting ban on females is maintained while further investigations of factors causing increased levels of natural mortality among females are undertaken. Synthesis and applications. At the flyway scale, continuous and accurate estimates of vital rates and the relative contribution of harvest versus other mortality causes are increasingly important as the population effect of adjusting harvest rates is most effectively evaluated within a model-based adaptive management framework.
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Insulin and other injectable biologic drugs have transformed the treatment of patients suffering from diabetes1,2, yet patients and healthcare providers often prefer to use and prescribe less effective orally dosed medications3-5. Compared with subcutaneously administered drugs, oral formulations create less patient discomfort4, show greater chemical stability at high temperatures6, and do not generate biohazardous needle waste7. An oral dosage form for biologic medications is ideal; however, macromolecule drugs are not readily absorbed into the bloodstream through the gastrointestinal tract8. We developed an ingestible capsule, termed the luminal unfolding microneedle injector, which allows for the oral delivery of biologic drugs by rapidly propelling dissolvable drug-loaded microneedles into intestinal tissue using a set of unfolding arms. During ex vivo human and in vivo swine studies, the device consistently delivered the microneedles to the tissue without causing complete thickness perforations. Using insulin as a model drug, we showed that, when actuated, the luminal unfolding microneedle injector provided a faster pharmacokinetic uptake profile and a systemic uptake >10% of that of a subcutaneous injection over a 4-h sampling period. With the ability to load a multitude of microneedle formulations, the device can serve as a platform to orally deliver therapeutic doses of macromolecule drugs.
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Administração Cutânea , Sistemas de Liberação de Medicamentos , Agulhas , Animais , Desenho de Equipamento , Humanos , Insulina/farmacologia , SuínosRESUMO
Biomacromolecules have transformed our capacity to effectively treat diseases; however, their rapid degradation and poor absorption in the gastrointestinal (GI) tract generally limit their administration to parenteral routes. An oral biologic delivery system must aid in both localization and permeation to achieve systemic drug uptake. Inspired by the leopard tortoise's ability to passively reorient, we developed an ingestible self-orienting millimeter-scale applicator (SOMA) that autonomously positions itself to engage with GI tissue. It then deploys milliposts fabricated from active pharmaceutical ingredients directly through the gastric mucosa while avoiding perforation. We conducted in vivo studies in rats and swine that support the applicator's safety and, using insulin as a model drug, demonstrated that the SOMA delivers active pharmaceutical ingredient plasma levels comparable to those achieved with subcutaneous millipost administration.
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Administração Oral , Sistemas de Liberação de Medicamentos/instrumentação , Insulina/administração & dosagem , Substâncias Macromoleculares/administração & dosagem , Animais , Insulina/sangue , Absorção Intestinal , Substâncias Macromoleculares/sangue , Poliésteres , Ratos , Aço Inoxidável , SuínosRESUMO
The great auk was once abundant and distributed across the North Atlantic. It is now extinct, having been heavily exploited for its eggs, meat, and feathers. We investigated the impact of human hunting on its demise by integrating genetic data, GPS-based ocean current data, and analyses of population viability. We sequenced complete mitochondrial genomes of 41 individuals from across the species' geographic range and reconstructed population structure and population dynamics throughout the Holocene. Taken together, our data do not provide any evidence that great auks were at risk of extinction prior to the onset of intensive human hunting in the early 16th century. In addition, our population viability analyses reveal that even if the great auk had not been under threat by environmental change, human hunting alone could have been sufficient to cause its extinction. Our results emphasise the vulnerability of even abundant and widespread species to intense and localised exploitation.
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Charadriiformes/genética , DNA Antigo/análise , Extinção Biológica , Dinâmica Populacional , Animais , DNA Mitocondrial , Variação Genética , Genoma Mitocondrial/genética , Humanos , FilogeniaRESUMO
Evolutionary theories of senescence predict that rates of decline in performance parameters should be shaped by early-life trade-offs between reproduction and somatic maintenance. Here we investigate factors influencing the rate of reproductive senescence in a long-lived seabird, the common guillemot Uria aalge, using data collected over a 23-year period. In the last 3 years of life, individual guillemots had significantly reduced breeding success and were less likely to hold a site or attempt to breed. Females senesced at a significantly faster rate than males. At the individual level, high levels of reproductive output earlier in life were associated with increased senescence later in life. This trade-off between early- and late-life reproduction was evident independent of the fact that as birds age, they breed later in the season. The rate of senescence was additionally dependent on environmental conditions experienced earlier in life, with evidence that harsh conditions amplified later declines in breeding success. Overall, individuals with intermediate levels of early-life productivity lived longer. These results provide support for the antagonistic-pleiotropy and disposable-soma theories of senescence and demonstrate for the first time in a wild bird population that increased rates of senescence in reproductive performance are associated with varying costs of reproduction early in life.
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Envelhecimento , Charadriiformes/fisiologia , Reprodução , Animais , Cruzamento , Meio Ambiente , Feminino , Longevidade , Masculino , Análise de Regressão , Comportamento Sexual Animal , Fatores de TempoRESUMO
Fisheries management across the world is moving toward an ecosystem-based approach, implying that fishery effects on nontarget species should be taken into account. However, such effects are often not well understood, partly because, they can be difficult to distinguish from impacts of environmental fluctuations. We evaluated the effects of an industrial sand lance (Ammodytes marinus) fishery off the North Sea coast of the United Kingdom, which has been opened and closed in a quasi-experimental fashion, on sand-lance-dependent breeding seabirds. Controlling for environmental variation (sea surface temperature, abundance of larval sand lance, and size of adult sand lance), we found that, when the fishery was operating, breeding productivity in the intensively studied seabird colony on the Isle of May was significantly depressed for one surface-feeding seabird species, the Black-legged Kittiwake (Rissa tridactyla), but not for four diving species. Analyzing Kittiwake data from 12 colonies inside and outside the closure zone in a replicated before-after control-impact design, we again found that breeding productivity was significantly depressed in the closure zone when the fishery was active, whereas no effect was found in the control zone. Furthermore, Kittiwake breeding productivity was negatively correlated with fishery effort during the fishery period in the closure zone, but not in the control zone. The contrasting findings in the two zones could be related to environmental differences or to the fact that only one study colony in the control zone was exposed to high fishery effort within the typical foraging range of Kittiwakes during the breeding season. The strong impact on Kittiwakes, but not on diving species, could result from (1) inherently high sensitivity to reduced prey availability, (2) changes in the vertical distribution of sand lance at lower densities, (3) sand lance showing avoidance behavior to fishery vessels, or a combination of some or all of these factors. These findings indicate that local fishery closures can benefit sensitive predators and should be considered as a tool for future ecosystem-based fisheries management.
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Charadriiformes/fisiologia , Pesqueiros , Peixes/fisiologia , Reprodução/fisiologia , Animais , Monitoramento Ambiental , Comportamento Alimentar , Dinâmica Populacional , Reino UnidoRESUMO
This paper provides a synthesis of the EU project MedVeg addressing the fate of nutrients released from fish farming in the Mediterranean with particular focus on the endemic seagrass Posidonia oceanica habitat. The objectives were to identify the main drivers of seagrass decline linked to fish farming and to provide sensitive indicators of environmental change, which can be used for monitoring purposes. The sedimentation of waste particles in the farm vicinities emerges as the main driver of benthic deterioration, such as accumulation of organic matter, sediment anoxia as well as seagrass decline. The effects of fish farming on P. oceanica meadows are diverse and complex and detected through various metrics and indicators. A safety distance of 400 m is suggested for management of P. oceanica near fish farms followed by establishment of permanent seagrass plots revisited annually for monitoring the health of the meadows.
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Alismatales/crescimento & desenvolvimento , Aquicultura , Ecossistema , Fezes/química , Peixes , Animais , Sedimentos Geológicos/análise , Mar Mediterrâneo , Dinâmica Populacional , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/análiseRESUMO
The Cormack-Jolly-Seber (CJS) model assumes that all marked animals have equal recapture probabilities at each sampling occasion, but heterogeneity in capture often occurs and should be taken into account to avoid biases in parameter estimates. Although diagnostic tests are generally used to detect trap-dependence or transience and assess the overall fit of the model, heterogeneity in capture is not routinely tested for. In order to detect and identify this phenomenon in a CJS framework, we propose a test of positive association between previous and future encounters using Goodman-Kruskal's gamma. This test is based solely on the raw capture histories and makes no assumption on model structure. The development of the test is motivated by a dataset of Sandwich terns (Thalasseus sandvicensis), and we use the test to formally show that they exhibit heterogeneity in capture. We use simulation to assess the performance of the test in the detection of heterogeneity in capture, compared to existing and corrected diagnostic goodness-of-fit tests, Leslie's test of equal catchability and Carothers' extension of the Leslie test. The test of positive association is easy to use and produces good results, demonstrating high power to detect heterogeneity in capture. We recommend using this new test prior to model fitting as the outcome will guide the model-building process and help draw more accurate biological conclusions. Supplementary materials accompanying this paper appear online. ELECTRONIC SUPPLEMENTARY MATERIAL: Supplementary materials for this article are available at 10.1007/s13253-017-0315-4.
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The impact of environmental change on animal populations is strongly influenced by the ability of individuals to plastically adjust key life-history events. There is therefore considerable interest in establishing the degree of plasticity in traits and how selection acts on plasticity in natural populations. Breeding time is a key life-history trait that affects fitness and recent studies have found that females vary significantly in their breeding time-environment relationships, with selection often favouring individuals exhibiting stronger plastic responses. In contrast, here, we show that although breeding time in the common guillemot, Uria aalge, is highly plastic at the population level in response to a large-scale environmental cue (the North Atlantic Oscillation, NAO), there is very little between-individual variation-most individuals respond to this climate cue very similarly. We demonstrate strong stabilizing selection against individuals who deviate from the average population-level response to NAO. This species differs significantly from those previously studied in being a colonial breeder, in which reproductive synchrony has a substantial impact on fitness; we suggest that counter selection imposed by a need for synchrony could limit individuals in their response and potential for directional selection to act. This demonstrates the importance of considering the relative costs and benefits of highly plastic responses in assessing the likely response of a population to the environmental change.