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Life history theory states that the resources invested in current reproduction must be traded off against resources needed for survival and future reproduction. Long-lived organisms have a higher residual reproductive value and are therefore expected to be sensitive to reproductive investments that may reduce survival and future reproduction. Individuals within a population may vary in phenotypic quality, experience, access to resources etc. This may affect their optimal reproductive investment level. In this study we manipulated reproductive costs by shortening and extending the incubation period in common eiders Somateria mollissima without altering clutch size. Females whose incubation time was prolonged experimentally, suffered higher mass loss and increased clutch loss/nest desertion. These females were also more prone to abandon their brood after hatching. Both clutch loss and brood abandonment decreased with clutch size in all treatment categories, indicating higher phenotypic quality and/or better access to resources for females producing more eggs. However, although females with prolonged incubation were lighter at hatching, their return rate and breeding performance in the following year were unaffected. These results show that individual quality as expressed through clutch size and body mass is affecting current reproductive investment level as well as future survival and breeding performance. The results also show that individual birds are sensitive to changes in their own condition, and when reproductive effort is approaching a level where survival or future survival may be compromised, they respond by terminating their current reproductive attempt.

1. Alien species constitute one of the major threats to global biodiversity. Stopping alien species at an early stage, preferably before establishment, is crucial for the effectiveness of management actions. To enable early detection and prevent future introductions, knowledge of pathways of introduction and their absolute and relative importance is crucial. 2. Based on an exhaustive impact assessment of alien species in Norway (all multicellular neobiota), the relations of taxonomy, lifestyle and ecological impact of alien species to their pathways of introduction are investigated. This taxonomically and ecologically unbiased dataset contains 2267 unique pathways of 1180 alien species. 3. Ecological and taxonomic patterns indicate that terrestrial organisms were predominantly introduced by means of escape (mainly perennial plants escaped from gardens), parasites as contaminants (mainly fungi and insects parasitising plants), freshwater organisms by release (mainly vertebrates) and marine organisms as stowaways (mainly invertebrates and algae). Unaided introductions were most common among insects and marine organisms. 4. Alien species with high ecological impact were mainly introduced along the same pathways as other alien species. In relative terms, high-impact species were overrepresented among released species, even though this pathway was subordinate in absolute terms. The number of pathways and the overall introduction pressure were important predictors of ecological impact, especially of the species' invasion potential, and area of occupancy. 5. Introduction rates of novel alien species have seen recent increases in all taxa and along almost all pathways. This acceleration was especially pronounced for insects and fungi introduced as contaminants and for marine organisms introduced as stowaways. In absolute terms, introduction rates were highest for plant escapes, reaching more than five novel species per year. 6. Synthesis and applications. Introductions of new alien species cannot be prevented by closing one or two introduction pathways, since none can be singled out as the main pathway of high-impact alien species. Yet each pathways closedmakes a difference, as this reduces the overall introduction pressure. The highest priorities for management are the pathways that are easiest to address, such as release, and those with the highest volumes, such as plant trade. ecological impact, escape, introduction pathway, invasive species, spread, stowaway

1. Invasive alien species are recognized as a significant anthropogenic threat to freshwater ecosystems, because they may bring about the local extinction of native species and the collapse of habitat types of special conservation concern. 2. The Water Framework Directive (WFD) is an important legislative tool for the protection of water bodies in the European Union. It requires the assessment of the ecological status of water bodies and the enforcement of measures for water bodies that fail to achieve at least ‘good’ ecological status. However, the WFD does not explicitly mention alien species. 3. This article presents a three-tiered approach for the incorporation of data on alien species into WFD assessments of freshwater bodies in Norway. If relevant data on WFD parameters are available for the water body under consideration, its ecological status should be inferred from those data. Otherwise, ecological status should be assessed using evidence of the effects that the alien species have on biological quality elements in comparable water bodies. If neither of these options is feasible, the ecological status should be classified according to the ecological effect score of the alien species present, as obtained from the Generic Ecological Impact Assessment of Alien Species (GEIAA). 4. It is further recommended that a water body cannot be assigned ‘high ecological status’ if at least one alien species is present. If more than one alien species is present, the status is determined by the species with the highest impact. 5. Ecological, geographical, historical, and taxonomic delimitation criteria for this assessment method are presented, together with a list of the alien species that at present fulfil these delimitations in Norway. 6. The management implications of the recommendations are that more Norwegian freshwater bodies are likely to require measures, and that further data must be collected. Most of the recommendations are transferable to other countries, although they may require adjustment. dispersal, ecological impact, freshwater bodies, invasive alien species, lakes, rivers

Climate change has considerably dominated science-policy dialogue, public debate, and subsequently environmental policies since the three “Rio Conventions” were born. This has led to practically independent courses of action of climate change mitigation and biodiversity conservation actions, neglecting potential conflicts among outcomes and with missed opportunities for synergistic measures. Transformative governance principles have been proposed to overcome these limitations. Using a transformative governance lens, we use the case of the Norwegian "Climate Cure 2030" for the Land Use, Land-Use Change and Forestry (LULUCF) sector to, first, illustrate the mechanisms that have led to the choice of climate mitigation measures; second, to analyze the potential consequences of these measures on biodiversity and greenhouse gas (GHG) emissions; and, third, to evaluate alternative measures with potential positive outcomes for biodiversity and GHG emissions/removals. We point to some mechanisms that could support the implementation of these positive actions.

The current warming of the oceans has been shown to have detrimental effects for a number of species. The understanding of the underlying mechanisms may be hampered by the non-linearity and non-stationarity of the relationships between temperature and demography, and by the insufficient length of available time series. Most demographic time series are too short to study the effect of climate on wildlife in the classical sense of meteorological patterns over at least 30 years. Here we present a harvest time series of Atlantic puffins (Fratercula arctica) that goes back as far as 1880. It originates in the world’s largest puffin colony, in southwest Iceland, which has recently experienced a strong decline. By estimating an annual chick production index for 128 years, we find prolonged periods of strong correlations between local sea surface temperature (SST) and chick production. The sign of decennial correlations switches three times during this period, where the phases of strong negative correlation between puffin productivity and SST correspond to the early 20th century Arctic warming period and to the most recent decades. Based on a shorter time series, one might have concluded that the correlation was uniformly negative or positive, or even absent. Most of the variation (72%) in chick production is explained by a model in which productivity peaks at an SST of 7.1 °C, clearly rejecting the assumption of a linear relationship. The SST at which the puffins’ production peaked has increased by 0.24 °C during the 20th century, although the increase in average SST during the same period has been more than three times faster. The best supported models indicate that the population’s decline is at least partially caused by the increasing SST around Iceland.

1. Due to globalisation, trade and transport, the spread of alien species is increasing dramatically. Some alien species become ecologically harmful by threatening native biota. This can lead to irreversible changes in local biodiversity and ecosystem functioning, and, ultimately, to biotic homogenisation. 2. We risk-assessed all alien plants, animals, fungi and algae, within certain delimitations, that are known to reproduce in Norway. Mainland Norway and the Arctic archipelago of Svalbard plus Jan Mayen were treated as separate assessment areas. Assessments followed the Generic Ecological Impact Assessment of Alien Species (GEIAA) protocol, which uses a fully quantitative set of criteria. 3. A total of 1519 species were risk-assessed, of which 1183 were species reproducing in mainland Norway. Among these, 9% were assessed to have a severe impact, 7% high impact, 7% potentially high impact, and 49% low impact, whereas 29% had no known impact. In Svalbard, 16 alien species were reproducing, one of which with a severe impact. 4. The impact assessments also covered 319 so-called door-knockers, i.e. species that are likely to establish in Norway within 50 years, and 12 regionally alien species. Of the door-knockers, 8% and 10% were assessed to have a severe and high impact, respectively. 5. The impact category of most species was driven by negative interactions with native species, transformation of threatened ecosystems, or genetic contamination. The proportion of alien species with high or severe impact varied significantly across the different pathways of introduction, taxonomic groups, time of introduction, and the environments colonised, but not across continents of origin. 6. Given the large number of alien species reproducing in Norway and the preponderance of species with low impact, it is neither realistic nor necessary to eradicate all of them. Our results can guide management authorities in two ways. First, the use of quantitative assessment criteria facilitates the prioritisation of management resources across species. Second, the background information collected for each species, such as introduction pathways, area of occupancy and ecosystems affected, helps designing appropriate management measures. 1. Globalisering, handel og transport fører til en dramatisk økning i spredningen av fremmede arter. Noen fremmede arter er skadelige og truer det stedegne naturmangfoldet. Lokalt kan dette medføre irreversible endringer i det lokale biologiske mangfoldet og økosystemenes funksjon; globalt en homogenisering av artssammensetningen. 2. Vi har gjennomført risikovurderinger av alle fremmede planter, dyr, sopper og alger som reproduserer i Norge og oppfyller visse avgrensninger. Svalbard og Jan Mayen ble behandla som et eget vurderingsområde, adskilt fra Fastlands‐Norge. Risikovurderingene ble gjort i tråd med GEIAA (Generic Ecological Impact Assessment of Alien Species), som benytter et rent kvantitativt kriteriesett. 3. Totalt ble 1519 arter risikovurdert, hvorav 1183 reproduserte i Fastlands‐Norge. Av disse ble 9 % vurdert til å utgjøre en svært høy risiko, 7 % en høy risiko, 7 % en potensielt høy risiko, 49 % en lav risiko og 29 % ingen kjent risiko. På Svalbard forekom 16 reproduserende fremmede arter, hvorav én med svært høy risiko. 4. Risikovurderingene omfatta også 319 såkalte dørstokkarter, dvs. fremmede arter som antas å kunne etablere seg i Norge innen 50 år, samt 12 regionalt fremmede arter. Blant dørstokkartene ble 8 % og 10 % vurdert til å utgjøre en svært høy respektive høy risiko. 5. For de fleste arter ble risikokategorien bestemt av artenes interaksjoner med stedegne arter, tilstandsendringer i trua naturtyper eller genetisk forurensning. Andelen av fremmede arter med høy eller svært høy risiko varierte signifikant på tvers av ulike introduksjonsveier, artsgrupper, tidspunkt for introduksjon og koloniserte naturtyper, men ikke på tvers av opphavsområder. 6. Gitt det store antallet av fremmede arter som reproduserer i Norge, og overvekten av arter som har lav risiko, er det verken realistisk eller nødvendig å utrydde alle. Resultatene våre kan hjelpe forvaltningsmyndighetene på to måter. For det første gjør bruken av kvantitative kriterier det lettere å prioritere ressurser på tvers av arter. For det andre kan passende forvaltningstiltak utarbeides på grunnlag av den innsamla bakgrunnsinformasjonen om artene, f.eks. deres spredningsveier, forekomstareal og berørte naturtyper. This is an open access article under the terms of the Creative Commons Attribution License, which permits use,distribution and reproduction in any medium, provided the original work is properly cited.c 2020 The Authors. Ecological Solutions and Evidence published by John Wiley & Sons Ltd on behalf of British Ecological Society

This is a post-peer-review, pre-copyedit version of an article published in Biological Invasions. The final authenticated version is available online at: https://doi.org/10.1007/s10530-019-02058-x. We present the results of an inventory and status assessment of alien species in Norway. The inventory covered all known multicellular neobiota, 2496 in total, 1039 of which were classified as naturalised. The latter constitute c. 3% of all species known to be stably reproducing in Norway. These figures are higher than expected from Norway’s latitude, which may be due a combination of climatic and historical factors, as well as sampling effort. Most of the naturalised neobiota were plants (71%),followed by animals (21%) and fungi (8%). The main habitat types colonised were open lowlands (79%), urban environments (52%) and woodlands (42%). The main areas of origin were Europe (67%), North America (15%) and Asia (13%). For most taxa, the rate of novel introductions seems to have been increasing during recent decades. Within Norway, the number of alien species recorded per county was negatively correlated with latitude and positively correlated with human population density. In the high-Arctic territories under Norwegian sovereignty, i.e. Svalbard and Jan Mayen, 104 alien species were recorded, of which 5 were naturalised.

The Generic Ecological Impact Assessment of Alien Species (GEIAA) is described. It comprises a set of criteria and an assessment procedure. The set of criteria consists of three criteria that quantify invasion potential, and six criteria that capture the ecological effects of alien species. The threshold values for all criteria are numerically defined, rendering the set of criteria fully quantitative. Genericity is ensured by using criteria that are applicable to all taxonomic groups and in all habitats. In being generic, quantitative, ecological and normatively neutral, the criteria were inspired by the international Red List criteria. Capturing both invasion potential and effect, GEIAA can be regarded as a full ecological impact assessment. The assessment procedure contains guidelines on documentation, the collection of background information, the handling of uncertainty, and quality assurance. GEIAA represents the second revision, and thus the third generation, of assessment methodology in Norway. It has recently been used to carry out more than 2500 impact assessments of alien species in Norway and Sweden. © The Author(s) 2019. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/)

The ecological impact of alien species is a function of the area colonised. Impact assessments of alien species are thus incomplete unless they take the spatial component of invasion processes into account. This paper describes a measure, termed expansion speed, that quantifies the speed with which a species increases its spatial presence in an assessment area. It is based on the area of occupancy (AOO) and can be estimated from grid occupancies. Expansion speed is defined as the yearly increase in the radius of a coherent circle having the same area as the AOO, irrespective of whether the increase is due to natural dispersal or anthropogenic transport. Two methods for estimating expansion speed are presented: one that requires several years of spatio-temporal observation data and explicitly takes detection rates into account; and one that can be used under a situation with sparse data. Using simulations and real-world data from natural history collections, it is shown that the method provides a good fit to observational datasets. Expansion speed has several valuable properties. Being based on AOO, it is an intuitive measure; as it only requires occupancy data, it is comparatively easy to estimate; and because it is a quantitative and generic measure, it increases the testability and comparability of impact assessments of alien species. Electronic supplementary material The online version of this article (10.1007/s10441-019-09366-8) contains supplementary material, which is available to authorized users.

The black-legged kittiwake Rissa tridactyla is a pelagic seabird whose population has recently declined in most parts of the North Atlantic and which is red-listed in most bordering countries. To investigate a possible cause for this decline, we analysed the population dynamics of 5 kittiwake colonies along the Norwegian coast, ranging from 62° to 71° N, over the last 20 to 35 yr. By quantifying the importance of sea surface temperatures (SST) in relevant areas of the North Atlantic, we tested the importance of climatic conditions throughout the populations’ annual cycles. We found no synchrony among colonies; however, SST affected population dynamics, explaining between 6% and 37% (average 18%) of the variation in annual population growth rate. While dynamics of the southerly colonies were mainly affected by winter conditions in the Grand Banks area, dynamics of the northernmost colonies were dominated by autumn conditions off Svalbard. Negative slopes indicated stronger population decline under warmer ocean conditions. Population dynamics were affected both via adult survival and offspring recruitment, as evidenced by the presence of unlagged effects as well as effects lagged by the age at recruitment. Finally, we performed population viability analyses taking into account the projected warming trends for the future. The median time to extinction of the Norwegian colonies was 52 to 181 yr without considering covariates; 45 to 94 yr when considering the effects of SST but ignoring future warming; and 10 to 48 yr when ocean warming, based on a ‘business as usual’ scenario, was taken into account. Global warming · Non-breeding distribution · Population dynamics · Population viability analysis · Rissa tridactyla · Sea surface temperature

The ecological impact assessment scheme that has been developed to classify alien species in Norway is presented. The underlying set of criteria enables a generic and semi-quantitative impact assessment of alien species. The criteria produce a classification of alien species that is testable, transparent and easily adjustable to novel evidence or environmental change. This gives a high scientific and political legitimacy to the end product and enables an effective prioritization of management efforts, while at the same time paying attention to the precautionary principle. The criteria chosen are applicable to all species regardless of taxonomic position. This makes the assessment scheme comparable to the Red List criteria used to classify threatened species. The impact of alien species is expressed along two independent axes, one measuring invasion potential, the other ecological effects. Using this two-dimensional approach, the categorization captures the ecological impact of alien species, which is the product rather than the sum of spread and effect. Invasion potential is assessed using three criteria, including expected population lifetime and expansion rate. Ecological effects are evaluated using six criteria, including interactions with native species, changes in landscape types, and the potential to transmit genes or parasites. Effects on threatened species or landscape types receive greater weightings.

Colonial breeding is an evolutionary puzzle, as the benefits of breeding in high densities are still not fully explained. Although the dynamics of existing colonies are increasingly understood, few studies have addressed the initial formation of colonies, and empirical tests are rare. Using a high-resolution larval drift model, we here document that the distribution of seabird colonies along the Norwegian coast can be explained by variations in the availability and predictability of fish larvae. The modelled variability in concentration of fish larvae is, in turn, predicted by the topography of the continental shelf and coastline. The advection of fish larvae along the coast translates small-scale topographic characteristics into a macroecological pattern, viz. the spatial distribution of top-predator breeding sites. Our findings provide empirical corroboration of the hypothesis that seabird colonies are founded in locations that minimize travel distances between breeding and foraging locations, thereby enabling optimal foraging by central-place foragers., Seabirds breed in high density colonies, but the factors determining colony position aren't clear. Here, Sandvik et al. show that small-scale coastal topography is related to likely variation in fish larval abundance, which predicts the distribution of seabird colonies along the Norwegian coast.

Climate variability can affect population dynamics via adult survival or via offspring production and recruitment. The relative importance of both processes is still an unresolved mat- ter, especially in long-lived species, where the time lags between the climate signal and the pop- ulation response differ greatly depending on the process involved. We address the issue using 378 time series from 29 seabird species from 187 breeding colonies throughout the North Atlantic. The effect of climate on population growth rate is estimated as the slope of the North Atlantic Oscilla- tion (NAO) index at different time lags when used as a covariate in population models. Using non- linear mixed effects models, we can demonstrate that climate affects the population dynamics of seabirds, both through adult survival and through the recruitment of offspring produced. The lat- ter effect is stronger, and the long time lags involved make it likely that its magnitude is still underestimated. Because different processes are involved, the sign of the relationship with the NAO differs between time lags. The relationship between the NAO and the population growth rate is also highly variable, both within and across species. In a second analytical step, we address the factors that may cause this interspecific and inter-colony variation, considering the ecological, demographic and geographical characteristics of the populations. Among comparatively 'fast- lived' seabirds, i.e. species with large clutches, the relationship with the NAO reverses its sign depending on latitude, while no such trend is apparent among 'slow' species.

Central to sexual selection theory is the question of when individuals should compete for mates. Theory predicts that the sex ratio of ready-to-mate individuals (operational sex ratio; OSR) affects male and female mating competition. In accordance with this, the strength of mating competition, measured by agonistic behaviors and courtship displays, has been found to co-vary with the OSR in field populations of several species. However, laboratory experiments have often produced results that seemingly contradict OSR theory, especially for courtship behavior. We argue that this may be because experiments typically measure frequencies of competitive behaviors. Frequencies of courtship and agonistic behavior are not only affected by the level of mating competition, but also by the number of potential mates or competitors encountered. In contrast, the propensity to behave competitively at a given encounter represents a behavioral response, and thus directly reflects mating competition. We show in 2 simple models that 1) courtship frequency can be expected to respond differently from courtship propensity to changes in OSR and 2) an increase in frequency of agonistic behaviors could occur even if the propensity is not affected by the OSR. In a meta-analysis of studies on courtship competition, we show that frequency measures produced largely opposite results to propensity measures, as predicted by our model. Moreover, courtship propensity increased when the OSR became more biased toward competitors. This presents strong evidence that the OSR affects competition, in the form of courtship, as predicted by OSR theory.

The purpose of the present study was to inspect the response of the Atlantic Puffin (Fratercula arctica) to an experimental manipulation of the investment needed to successfully raise an offspring. We achieved this by replacing an old offspring with a younger chick, and vice versa, thereby prolonging and shortening the chick-rearing period. To examine any costs of reproduction we then followed the breeding success, the recruitment of young to the population, and the survival of parents for 11 years following the manipulation. Parents in the prolonged and shortened category had a lower breeding success than controls mainly because parents deserted their chick shortly after swapping. Among those that raised their chick, the age and body mass of foster chicks at fledging were the same in all three categories even though the parents had raised chicks for different lengths of time. The recruitment of young to the breeding population was high and independent of treatment. Likewise, the survival of adults was independent of treatment. For the 11 years after the experiment, however, the resighting rate of those that deserted their chick was clearly lower than among those that accepted their foster chick. For parents that raised their foster chick, the survival to the following year was positively related to their body mass. The results support the hypothesis that puffins have a highly flexible parental investment, which they adjust according to their own individual quality and the survival prospects of the chick.

Survival from fledging to maturity is an important life-history parameter in long-lived species such as seabirds. However, because of the long period of unobservability following fledging, few studies have reported reliable estimates of survival rates for immatures. We estimated survival to maturity of two cohorts of Atlantic Puffin (Fratercula arctica) fledglings from Hornoya in northern Norway using capture–mark–recapture methodology. By considering only juveniles that actually left their nest burrows, we arrived at unbiased estimates of survival rates for immatures. Contrary to many previous studies, annual survival of immatures was not depressed in relation to adult survival. By the age of five years, more than two-thirds of all fledglings are still estimated to be alive. Averaged over this period, annual survival of immatures is estimated as 0.933 (95% confidence interval: 0.806–0.993). This compares to an annual adult survival of 0.943 (0.909–0.965) during the same period. The survival esti...

It has been shown previously that the awareness and concern of the general public about global warming is not only a function of scientific information. Both psychological and sociological factors affect the willingness of laypeople to acknowledge the reality of global warming, and to support climate policies of their home countries. In this paper, I analyse a cross-national dataset of public concern about global warming, utilising data from 46 countries. Based on earlier results at the national and regional level, I expect concern to be negatively correlated to national measures of wealth and carbon dioxide emissions. I find that gross domestic product is indeed negatively correlated to the proportion of a population that regards global warming as a serious problem. There is also a marginally significant tendency that nations' per capita carbon dioxide emissions are negatively correlated to public concern. These findings suggest that the willingness of a nation to contribute to reductions in greenhouse gas emissions decreases with its share of these emissions. This is in accordance with psychological findings, but poses a problem for political decision-makers. When communicating with the public, scientists ought to be aware of their responsibility to use a language that is understood by laypeople.

For an understanding of the effect of climate change on animal population dynamics, it is crucial to be able to identify which climatologic parameters affect which demographic rate, and what the underlying mechanistic links are. An important reason for why the interactions between demography and climate still are poorly understood is that the effects of climate vary both geographically and taxonomically. Here, we analyse interspecifically how different climate variables affect the breeding success of North Atlantic seabird species along latitudinal and longitudinal gradients. By approaching the problem comparatively, we are able to generalize across populations and species. We find a strong interactive effect of climate and latitude on breeding success. Of the climatic variables considered, local sea surface temperatures during the breeding season tend to be more relevant than the North Atlantic Oscillation (NAO). However, the effect of NAO on breeding success shows a clear geographic pattern, changing in sign from positive in the south to negative in the north. If this interaction is taken account of, the model explains more variation than any model with sea surface temperature. This superiority of the NAO index is due to its ability to capture effects of more than one season in a single parameter. Mechanistically, however, several lines of evidence suggest that sea surface temperature is the biologically most relevant explanatory variable.

In the light of the predicted changes in climate as a consequence of global warming, it is a major concern how animal species will respond to altered meteorological and oceanographic conditions. Seabirds constitute a diverse group of marine top predators which have relatively low fecundity and high annual survival rates. In order to predict effects of climate change, it is a necessary precondition to first understand responses to naturally occurring climatic fluctuations. While the ecological effects of different large-scale climatic phenomena have received much attention in the recent past, the factors determining the responses of seabirds are still little understood. We analyze more than a hundred previously published time series of seabird offspring production and adult survival rates in the North Atlantic in order to detect climatic signals in this data base. As our analyses are phylogenetic-comparative, we are able to search for patterns across species. Using the correlation of these parameters with the North Atlantic Oscillation (NAO) as a measure of responsiveness to climatic variability, we find that effects of climate on either parameters considered are not more common than expected by chance. The magnitudes of the responsivenesses were not entirely randomly distributed throughout the seabird phylogeny, but were not strongly related to the explanatory variables considered. However, some tendencies indicate that both life-history traits and feeding ecology may influence how seabirds respond to climatic variability. An explanation of those patterns based on life-history theory is given.

In many seabird studies, single annual proxies of prey abundance have been used to explain variability in breeding performance, but much more important is probably the timing of prey availability relative to the breeding season when energy demand is at a maximum. Until now, intraseasonal variation in prey availability has been difficult to quantify in seabirds. Using a state-of-the-art ocean drift model of larval cod Gadus morhua, an important constituent of the diet of common guillemots Uria aalge in the southwestern Barents Sea, we were able to show clear, short-term correlations between food availability and measurements of the stress hormone corticosterone (CORT) in parental guillemots over a 3-year period (2009–2011). The model allowed the extraction of abundance and size of cod larvae with very high spatial (4 km) and temporal resolutions (1 day) and showed that cod larvae from adjacent northern spawning grounds in Norway were always available near the guillemot breeding colony while those from more distant southerly spawning grounds were less frequent, but larger. The latter arrived in waves whose magnitude and timing, and thus overlap with the guillemot breeding season, varied between years. CORT levels in adult guillemots were lower in birds caught after a week with high frequencies of southern cod larvae. This pattern was restricted to the two years (2009 and 2010) in which southern larvae arrived before the end of the guillemot breeding season. Any such pattern was masked in 2011 by already exceptionally high numbers of cod larvae in the region throughout chick-rearing period. The findings suggest that CORT levels in breeding birds increase when the arrival of southern sizable larvae does not match the period of peak energy requirements during breeding. Common guillemot, CORT, food availability, seabird, Uria aalge © 2015 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

What is the Largest animal taxon? The most famous answer to this ques- tion has been given by Haldane who coined the phrase that 'the Creator has an inordinate fondness for beetles'. Although much cited, this statement has never been tested. Other experts have suggested other candidates for the largest animal taxon, all of which included the beetles as a subordinate group. I here outline a novel phylogenetic-comparative method that can address the question in a testable way. The result of applying the algorithm to the Metazoa is astonishing: the largest animal taxon is neither beetles nor a taxon super- or subordinated to beetles, but the Mecopteriformia.

Summary 1 In long-lived species, adult survival is an important life-history trait. Better knowledge of the effects of non-catastrophic climate variation on the adult survival of long-lived seabirds is therefore needed. However, documentation of such effects is still rare. 2 Using capture–mark–resighting data, we modelled the annual survival rates of five species of seabirds, the common guillemot (Uria aalge), Brunnich's guillemot (Uria lomvia), razorbill (Alca torda), Atlantic puffin (Fratercula arctica) and black-legged kittiwake (Rissa tridactyla). The data spanned 14 years of observation at a colony on Hornoya, off Northern Norway in the western Barents Sea. 3 A method of taking into account ring-loss of marked individuals is proposed. This approach made it possible to keep many observations which otherwise would have to be discarded. 4 The estimated survival rates were higher and less variable than most estimates for the same species from other colonies. There was extensive resighting heterogeneity. Ignoring this effect would have underestimated breeding life span by more than 50% in some species. 5 The analysis presented is the first study to document a correlation between the North Atlantic Oscillation (NAO) index and adult survival in North Atlantic seabirds. Other environmental variables considered were sea surface temperatures (SST) and prey stocks. In most of the species, models incorporating climatological variables were considerably better supported than models with constant survival, time-dependent survival or prey effects. SSTs tended to explain more of the variability in seabird survival than did the NAO. 6 The importance of prey availability was evident in some of the species, but climate was generally a better predictor of survival. Nevertheless, the evidence suggests that meteorological parameters affect seabird mortality only indirectly, possibly through the food chain. This conclusion rests on the observations that most NAO effects are lagged, and that survival rates decreased with increasing SSTs.

In migratory birds, environmental conditions in both breeding and non-breeding areas may affect adult survival rates and hence be significant drivers of demographic processes. In seabirds, poor knowledge of their true distribution outside the breeding season, however, has severely limited such studies. This study explored how annual adult survival rates of black-legged kittiwakes Rissa tridactyla on Hornøya in the southern Barents Sea were related to temporal variation in prey densities and climatic parameters in their breeding and non-breeding areas. We used information on the kittiwakes’ spatiotemporal distribution in the non-breeding season gained from year-round light-based tracking devices (geolocators) and satellite transmitters, and kittiwake annual adult survival rates gained from a multistate capture-mark-recapture analysis of a 22 yr time series of colour-ringed kittiwakes. In the post-breeding period, kittiwakes concentrated in an area east of Svalbard, in the winter they stayed in the Grand Banks/Labrador Sea area, and in the pre-breeding period they returned to the Barents Sea. We identified 2 possible prey categories of importance for the survival of kittiwakes in these areas (sea butterflies Thecosomata in the Grand Banks/Labrador Sea area in winter and capelin Mallotus villosus in the Barents Sea in the pre-breeding season) that together explained 52% of the variation in adult survival rates. Our results may have important implications for the conservation of kittiwakes, which are declining globally, because other populations use the same areas. Since they are under the influence of major anthropogenic activities including fisheries, international shipping and the offshore oil and gas industry, both areas should be targeted for future management plans. Black-legged kittiwake · Pteropods · Capelin · Capture-mark-recapture analyses · Non-breeding distribution

The effect of investigator activity on Black-legged Kittiwakes (Rissa tridactyla) was assessed using the disturbance caused by an ongoing intensive study investigating chick growth and adult mass loss. Though the effects were small, investigator disturbance decreased adult nest attendance and increased daily chick loss rates. Whereas overall chick survival until day 18 post-hatch was significantly lower in the high-disturbance plot in the first year of the study, it was substantially higher in the second year. We hypothesize that changes in predator activity as an indirect consequence of disturbance were responsible for this pattern. Herring Gulls (Larus argentatus) which nested near the high-disturbance plot and are the main predator of kittiwakes in our study area may have been more susceptible to the effect of disturbance than the kittiwakes themselves. There was otherwise no statistically significant impact of disturbance on chick growth, or on adult kittiwakes extending into the following ye...

In long-lived species, any negative effect of pollution on adult survival may pose serious hazards to breeding populations. In this study, we measured concentrations of various organochlorines (OCs) (polychlorinated biphenyl and OC pesticides) in the blood of a large number of adult glaucous gulls ( Larus hyperboreus ) breeding on Bjørnøya (Bear Island) in the Norwegian Arctic, and modelled their local survival using capture–recapture analysis. Survival was negatively associated with concentrations of OCs in the blood. The effect of OCs was nonlinear and evident only among birds with the highest concentrations (the uppermost deciles of contamination). The threshold for depressed survival differed between the sexes, with females being more sensitive to contamination. For birds with lower OC concentration, survival was very high, i.e. at the upper range of survival rates reported from glaucous and other large gull species in other, presumably less contaminated populations. We propose two non-exclusive explanations. First, at some threshold of OC concentration, parents (especially males) may abandon reproduction to maximize their own survival. Second, high contamination of OC may eliminate the most sensitive individuals from the population (especially among females), inducing a strong selection towards high-quality and less sensitive phenotypes.

A major challenge in population ecology is the prediction of population responses to environmental variance. Food availability has long been hypothesized to play a major role in regulating seabird populations. In general, seabirds feed on small pelagic fish and/or young age classes of larger predatory fish. Here we used a logistic population model to predict the temporal variation in the population size of common guillemots Uria aalge in a colony in NE Norway (Hornøya) between 1987 and 2011 in relation to the variation in abundance (acoustic and trawl surveys) of important fish prey species in the Barents Sea. The fish species considered, all of which have been described in the diet of common guillemot chicks and adults on Hornøya, were capelin Mallotus villosus (all age classes), 1-group herring Clupea harengus and 0-group cod Gadus morhua. The guillemot population collapsed by more than 80% during the winter 1986/1987, when the abundance indices of all fish prey species were very low, but has since steadily increased. The annual variation in population growth rate after the population collapse could best be explained by the variation in abundance of 0-group cod (unlagged), and the 0-group cod and capelin 6 and 4 yr earlier, respectively (equalling the age of maturation of guillemots). We also present a numerical ocean model to identify mechanisms affecting spatio-temporal prey availability of 0-group cod around the colony during the breeding season. These results undermine earlier focus on the capelin stock as the main cause of the population crash in common guillemots. 2018-02-14

Climate variability influences seabird population dynamics in several ways including access to prey near colonies during the critical chick-rearing period. This study addresses breeding success in a Barents Sea colony of common guillemots Uria aalge where trophic conditions vary according to changes in the northward transport of warm Atlantic Water. A drift model was used to simulate interannual variations in transport of cod Gadus morhua larvae along the Norwegian coast towards their nursery grounds in the Barents Sea. The results showed that the arrival of cod larvae from southern spawning grounds had a major effect on the size of common guillemot chicks at fledging. Furthermore, the fraction of larvae from the south was positively correlated to the inflow of Atlantic Water into the Barents Sea thus clearly demonstrating the mechanisms by which climate-driven bottom-up processes influence interannual variations in reproductive success in a marine top predator.

In two recent issues of Conservation Biology , Gehrt (1996) and Kay (1997) discussed some aspects of the “human population problem.” Gehrt advocated the promotion of education and ecocentric ethics to change human population growth and behavior. Kay suggested, on the other hand, that a human population problem does not exist because the real problem is evolution by natural selection. Therefore, neither education nor ethics can offer solutions. I comment on both contributions and correct some misconceptions, especially one about “the laws of evolution.” More specifically, I want to address (1) what the human population problem consists of and (2) whether it really is a problem of natural selection.