37 Works

Immunosenescence in the wild? A longitudinal study in a long‐lived seabird

Coraline Bichet, Maria Moiron, Kevin D. Matson, Oscar Vedder & Sandra Bouwhuis
1. Longitudinal studies of various vertebrate populations have demonstrated senescent declines in reproductive performance and survival probability to be almost ubiquitous. Longitudinal studies of potential underlying proximate mechanisms, however, are still scarce. 2. Due to its critical function in the maintenance of health and viability, the immune system is among the potential (mediators of) proximate mechanisms that could underlie senescence. 3. Here, we studied three innate immune parameters - hemagglutination titre, haemolysis titre and haptoglobin...

Data from: When and where does mortality occur in migratory birds? Direct evidence from long-term satellite tracking of raptors

Raymond H. G. Klaassen, Michael Hake, Roine Strandberg, Ben J. Koks, Christiane Trierweiler, Klaus-Michael Exo, Franz Bairlein, Thomas Alerstam & Mikael Hake
1. Information about when and where animals die is important to understand population regulation. In migratory animals, mortality might occur not only during the stationary periods (e.g. breeding and wintering) but also during the migration seasons. However, the relative importance of population limiting factors during different periods of the year remains poorly understood, and previous studies mainly relied on indirect evidence. 2. Here we provide direct evidence about when and where migrants die by identifying...

Data from: A hidden cost of migration? Innate immune function versus antioxidant defense

Cas Eikenaar, Caroline Isaksson & Arne Hegemann
Migration is energetically demanding and physiologically challenging. Migrating birds, for example, need to boost their antioxidant defenses to defeat the pro-oxidants produced during high energetic activity. The enhanced antioxidant defense possibly withdraws limited resources (e.g. energy or micronutrients) from other physiological functions, such as immune defense. Such a trade-off might not occur outside the migration seasons or in resident individuals. Here, we investigate if there is a negative relationship between innate immune function and antioxidant...

Data from: The avian lightweights: trans-Saharan migrants show lower lean body mass than short-/medium-distance migrants

Natalie Kelsey, Heiko Schmaljohann & Franz Bairlein
Avian trans-Saharan migrants travelling long distances and crossing ecological barriers experience different constraints in terms of time, energy and safety than short-/medium-distance migrants without barrier-crossings. As such, natural selection shapes the aerodynamic properties of these groups differently. Yet, to the best of our knowledge, we lack information on whether natural selection has contributed to reducing energetic flight costs through generally lower body mass in trans-Saharan migrants. To fill parts of this gap, we investigated this...

Data from: No effect of partner age and lifespan on female age-specific reproductive performance in blue tits

Seyed Mehdi Amininasab, Martijn Hammers, Oscar Vedder, Jan Komdeur & Peter Korsten
Studies of age-specific reproductive performance are fundamental to our understanding of population dynamics and the evolution of life-history strategies. In species with bi-parental care, reproductive ageing trajectories of either parent may be influenced by their partner's age, but this has rarely been investigated. We investigated within-individual age-specific performance (laying date and number of eggs laid) in wild female blue tits Cyanistes caeruleus and evaluated how the age and longevity of their male partner indirectly influenced...

Data from: Telomere attrition and growth: a life-history framework and case study in common terns

Oscar Vedder, Simon Verhulst, Christina Bauch & Sandra Bouwhuis
The relationship between growth and age-specific telomere length, as a proxy of somatic state, is increasingly investigated, but observed patterns vary and a predictive framework is lacking. We outline expectations based on the assumption that telomere maintenance is costly and argue that individual heterogeneity in resource acquisition is predicted to lead to positive covariance between growth and telomere length. However, canalization of resource allocation to the trait with a larger effect on fitness, rendering that...

Data from: Reduced telomere length in offspring of old fathers in a long-lived seabird

Sandra Bouwhuis, Simon Verhulst, Christina Bauch & Oscar Vedder
Evidence for transgenerational effects of senescence, whereby offspring from older parents have a reduced lifetime reproductive success, is increasing. Such effects could arise from compromised germline maintenance in old parents, potentially reflected in reduced telomere length in their offspring. We test the relationship between parental age and offspring early-life telomere length in a natural population of common terns and find a significant negative correlation between paternal age and offspring telomere length. Offspring telomere length is...

Data from: The diversity of population responses to environmental change

Fernando Colchero, Owen R. Jones, Dalia A. Conde, Dave Hodgson, Felix Zajitschek, Benedikt R. Schmidt, Aurelio F. Malo, Susan C. Alberts, Peter H. Becker, Sandra Bouwhuis, Anne M. Bronikowski, Kristel M. De Vleeschouwer, Richard J. Delahay, Stefan Dummermuth, Eduardo Fernández-Duque, John Frisenvænge, Martin Hesselsøe, Sam Larson, Jean-Francois Lemaitre, Jennifer McDonald, David A.W. Miller, Colin O'Donnell, Craig Packer, Becky E. Raboy, Christopher J. Reading … & Chris J. Reading
The current extinction and climate change crises pressure us to predict population dynamics with ever-greater accuracy. Although predictions rest on the well-advanced theory of age-structured populations, two key issues remain poorly-explored. Specifically, how the age-dependency in demographic rates and the year-to-year interactions between survival and fecundity affect stochastic population growth rates. We use inference, simulations, and mathematical derivations to explore how environmental perturbations determine population growth rates for populations with different age-specific demographic rates and...

Data from: Lifespan and reproductive cost explain interspecific variation in the optimal onset of reproduction

Emeline Mourocq, Pierre Bize, Sandra Bouwhuis, Russell Bradley, Anne Charmantier, Carlos De La Cruz, Szymon Marian Obniak, Richard H. M. Espie, Márton Herenyi, Hermann Hötker, Oliver Kruger, John Marzluff, Anders P. Møller, Shinichi Nakagawa, Richard A. Phillips, Andrew N. Radford, Alexandre Roulin, János Török, Juliana Valencia, Martijn Van De Pol, Ian G. Warkentin, Isabel S. Winney, Andrew G. Wood, Michael Griesser & Szymon M. Drobniak
Fitness can be profoundly influenced by the age at first reproduction (AFR), but to date the AFR-fitness relationship only has been investigated intraspecifically. Here we investigated the relationship between AFR and average lifetime reproductive success (LRS) across 34 bird species. We assessed differences in the deviation of the Optimal AFR (i.e., the species-specific AFR associated with the highest LRS) from the age at sexual maturity, considering potential effects of life-history as well as social and...

How fitness consequences of early-life conditions vary with age in a long-lived seabird: a Bayesian multivariate analysis of age-specific reproductive values

Oscar Vedder, Ido Pen & Sandra Bouwhuis
Evolutionary theory suggests that individuals can benefit from deferring the fitness cost of developing under poor conditions to later in life. Although empirical evidence for delayed fitness costs of poor developmental conditions is abundant, individuals that die prematurely have not often been incorporated when estimating fitness, such that age-specific fitness costs, and therefore the relative importance of delayed fitness costs is actually unknown. We developed a Bayesian statistical framework to estimate age-specific reproductive values in...

Data from: Potential age differences in the migratory behaviour of a nocturnal songbird migrant during autumn and spring

Heiko Schmaljohann, Florian Müller, Thomas Klinner & Cas Eikenaar
In migratory songbirds, older individuals are thought to be more efficient migrants than younger individuals. Age-specific differences in migratory efficiency have been reported mainly in respect of arrival timing, energy stores, rate of energy accumulation, departure behaviour, and departure direction. Yet, these traits were rarely assessed simultaneously in a single species. We further lack information whether age-specific differences in behavioural traits present in autumn still manifest to the same degree in spring. Here we used...

Data from: Nocturnal departure timing in songbirds facing distinct migratory challenges

Florian Müller, Cas Eikenaar, Zoe J. Crysler, Philip D. Taylor & Heiko Schmaljohann
1. Most migratory songbirds travel between their breeding areas and wintering grounds through a series of nocturnal flights. The timing of their departures defines the potential flight duration and thus the distance covered during a migratory night. Yet, migratory songbirds show substantial variation in their nocturnal departure timing. 2. With this study we aim to assess whether the respective challenges of the migration route, namely its distance and nature, help to explain this variation. 3....

Data from: Within the genome, long telomeres are more informative than short telomeres with respect to fitness components in a long-lived seabird

Christina Bauch, Peter H. Becker & Simon Verhulst
Telomeres, DNA-protein structures at chromosome ends, shorten with age, and telomere length has been linked to age-related diseases and survival. In vitro studies revealed that the shortest telomeres trigger cell senescence, but whether the shortest telomeres are also the best biomarker of ageing is not known. We measured telomeres in erythrocytes of wild common terns Sterna hirundo using terminal restriction fragment analysis. This yields a distribution of telomere lengths for each sample, and we investigated...

Data from: Telomere length is repeatable, shortens with age and reproductive success, and predicts remaining lifespan in a long-lived seabird

Coraline Bichet, Sandra Bouwhuis, Christina Bauch, Simon Verhulst, Peter Becker & Oscar Vedder
Telomeres are protective caps at the end of chromosomes, and their length is positively correlated with individual health and lifespan across taxa. Longitudinal studies have provided mixed results regarding the within-individual repeatability of telomere length. While some studies suggest telomere length to be highly dynamic and sensitive to resource-demanding or stressful conditions, others suggest that between-individual differences are mostly present from birth and relatively little affected by the later environment. This dichotomy could arise from...

Migrant blackbirds, Turdus merula, have higher plasma levels of polyunsaturated fatty acids compared to residents, but not enhanced fatty acid unsaturation index

Johan Kjellberg Jensen, Caroline Isaksson, Cas Eikenaar & Martin N. Andersson
Birds have been observed to have dietary preferences for unsaturated fatty acids during migration. Polyunsaturated fatty acids (PUFAs) may increase the exercise performance of migrant birds; however, PUFAs are also peroxidation prone and might therefore incur increased costs in terms of enhanced oxidative damage in migratory individuals. To shed light on this potential constraint, we analysed plasma fatty acid (FA) composition and estimated the unsaturation index as a proxy for susceptibility to lipid peroxidation of...

Changes in fat mass and migratory restlessness in northern wheatears

Cas Eikenaar, Thiemo Karwinkel & Sven Hessler
To fuel their migratory endurance flights, most birds accumulate large quantities of fat prior to departure. It therefore seems logical that the decision to depart on a migratory flight depends on fuel stores, at least to some extent; very small fuel stores prohibit migratory endurance flight. However, studies linking migrants’ estimated fuel stores (or sometimes actual fat stores) to departure likelihood have provided inconsistent results. Fuel stores are not static though, but highly dynamic. Instead...

Data from: Contrasting heterozygosity-fitness correlations across life in a long-lived seabird

Coraline Bichet, Oscar Vedder, Hedwig Sauer-Gürth, Peter H. Becker, Michael Wink & Sandra Bouwhuis
Selection is a central force underlying evolutionary change and can vary in strength and direction, for example across time and space. The fitness consequences of individual genetic diversity have often been investigated by testing for multi-locus heterozygosity-fitness correlations (HFCs), but few studies have been able to assess HFCs across life stages and in both sexes. Here, we test for HFCs using a 26-year longitudinal individual-based dataset from a large population of a long-lived seabird (the...

Data from: Ecological causes of multi-level covariance between size and first-year survival in a wild bird population

Sandra Bouwhuis, Oscar Vedder, Colin J. Garroway & Ben C. Sheldon
1. Estimates of selection in natural populations are frequent but our understanding of ecological causes of selection, and causes of variation in the direction, strength and form of selection, is limited. 2. Here, we apply a multi-level framework to partition effects of great tit fledging mass on first-year survival to hierarchical levels and quantify their ecological dependence using a data set spanning 51 years. 3. We show that estimates of the effect of fledging mass...

Data from: Sex-specific pathways of parental age effects on offspring lifetime reproductive success in a long-lived seabird

Sandra Bouwhuis, Oscar Vedder & Peter H. Becker
The conditions under which individuals are reared vary and sensitivity of offspring to such variation is often sex-dependent. Parental age is one important natal condition with consequences for aspects of offspring fitness, but reports are mostly limited to short-term fitness consequences and do not take into account offspring sex. Here we used individual-based data from a large colony of a long-lived seabird, the common tern Sterna hirundo, to investigate longitudinal long-term fitness consequences of parental...

Data from: Age-dependent trait variation: the relative contribution of within-individual change, selective appearance and disappearance in a long-lived seabird

He Zhang, Oscar Vedder, Peter H. Becker & Sandra Bouwhuis
1. Within populations, the expression of phenotypic traits typically varies with age. Such age-dependent trait variation can be caused by within-individual change (improvement, senescence, terminal effects) and/or selective (dis)appearance of certain phenotypes among older age classes. 2. In this study we applied two methods (decomposition and mixed-modelling) to attribute age-dependent variation in seven phenological and reproductive traits to within-individual change and selective (dis)appearance, in a long-lived seabird, the common tern (Sterna hirundo). 3. At the...

Data from: Male-biased sex allocation in ageing parents; a longitudinal study in a long-lived seabird

Oscar Vedder, Sandra Bouwhuis, Maria M. Benito & Peter H. Becker
Optimal sex allocation is frequency-dependent, but senescence may cause behaviour at old age to be suboptimal. We investigated whether sex allocation changes with parental age, using 16 years of data comprising more than 2500 molecularly sexed offspring of more than 600 known-age parents in common terns (Sterna hirundo), slightly sexually size-dimorphic seabirds. We decomposed parental age effects into within-individual change and sex allocation-associated selective (dis)appearance. Individual parents did not differ consistently in sex allocation, but...

Data from: Food quality and quantity is more important in explaining foraging of an intermediate-sized mammalian herbivore than predation risk or competition

Martijn J.A. Weterings, Sander Moonen, Herbert H.T. Prins, Sipke E. Van Wieren, Frank Van Langevelde, Martijn J. A. Weterings & Herbert H. T. Prins
During times of high activity by predators and competitors, herbivores may be forced to forage in patches of low-quality food. However, the relative importance in determining where and what herbivores forage still remains unclear, especially for small and intermediate-sized herbivores. Our objective was to test the relative importance of predator and competitor activity, and forage quality and quantity on the proportion of time spent in a vegetation type and the proportion of time spent foraging...

Data from: Better the devil you know: common terns stay with a previous partner although pair bond duration does not affect breeding output

Maren Rebke, Peter H. Becker & Fernando Colchero
In a monogamous species two partners contribute to the breeding process. We study pair formation as well as the effect of pair bond length and age on breeding performance, incorporating individual heterogeneity, based on a high-quality dataset of a long-lived seabird, the common tern (Sterna hirundo). To handle missing information and model the complicated processes driving reproduction, we use a hierarchical Bayesian model of the steps that lead to the number of fledglings, including processes...

Data from: Faster spring migration in northern wheatears is not explained by an endogenous seasonal difference in refueling rates

Cas Eikenaar, Arseny Tsvey & Heiko Schmaljohann
A widespread phenomenon in migrant birds is that they travel faster in spring than in autumn. During migration birds spend most time at stopover sites and, correspondingly, the faster spring migration is mainly explained by shorter stopovers in spring than autumn. Because a main purpose of stopovers is to replenish the fuel used in flight, a higher rate of fuel deposition (FDR) in spring is thought to explain the shorter stopovers and hence shorter total...

Data from: Telomere length reflects reproductive effort indicated by corticosterone levels in a long-lived seabird

Christina Bauch, Juliane Riechert, Simon Verhulst & Peter H. Becker
Telomere length (TL) is a candidate biomarker of ageing and phenotypic quality, but little is known of the (physiological) causes of TL variation. We previously showed that individual common terns Sterna hirundo with high reproductive success had short telomeres independent of age, and this pattern was particularly strong in the longer telomeres of the within-individual TL distribution. To test whether this relation can be attributed to effects of reproductive effort, we investigated baseline corticosterone in...

Registration Year

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  • 2012

Resource Types

  • Dataset


  • Institute of Avian Research
  • University of Groningen
  • Lund University
  • University of Exeter
  • University of Oxford
  • Centre d'Ecologie Fonctionnelle et Evolutive
  • British Antarctic Survey
  • University of Oslo
  • University of Zurich
  • Bielefeld University