Jacques Blondel

French National Centre for Scientific Research | CNRS · Centre d'Ecologie Fonctionnelle et Evolutive

Photo: Nicolas Lambrechts

Example of a great tit nest of which a nest cup has been built on top of a thick layer of pine needles. This nest type illustrates that the nest cup and its components mainly contribute to the protection of eggs and nestlings. Experiments of which boxes are filled up with a pine needles could be used to facilitate the study of the biological conseq...

We studied the relationship between temperature and the coexistence of great tit Parus major and blue tit Cyanistes caeruleus, breeding in 75 study plots across Europe and North Africa. We expected an advance in laying date and a reduction in clutch size during warmer springs as a general response to climate warming and a delay in laying date and a...

Cambridge Core - Natural Resource Management, Agriculture, Horticulture and forestry - Ecology and Conservation of Forest Birds - edited by Grzegorz Mikusiński

Evolutionary adaptation as a response to climate change is expected for fitness-related traits affected by climate and exhibiting genetic variance. Although the relationship between warmer spring temperature and earlier timing of reproduction is well documented, quantifications and predictions of the impact of global warming on natural selection ac...

Investigations of urbanization effects on birds have focused mainly on breeding traits expressed after the nest-building stage (e.g. first-egg date, clutch size, breeding success, and offspring characteristics). Urban studies largely ignored how and why the aspects of nest building might be associated with the degree of urbanization. As urban envir...

Avian nests function to provide a safe environment for parents, eggs and nestlings. Positive associations between nest size and other components of breeding performance are expected in two conditions. First, larger nests protect nest occupants better against environmental fluctuations (e.g., weather) than smaller nests. This implies that nest size...

The increase in size of human populations in urban and agricultural areas has resulted in considerable habitat conversion globally. Such anthropogenic areas have specific environmental characteristics, which influence the physiology, life history, and population dynamics of plants and animals. For example, the date of bud burst is advanced in urban...

Figure S1. Intensity of urbanisation according to (A) classification by scientists. Box plots show medians, quartiles, 5‐ and 95‐percentiles, and extreme values, and (B) CORINE land cover code (red = discontinuous urban, purple = industrial or commercial units, pink = green urban sites, brown = arable land and rice field, orange = agriculture lands...

Figure S2. Distribution of study plots across Europe, North Africa and the Middle East.

Table S1. Summary data for study plots. See Material and methods for definitions. Table S2. Correlation matrix of explanatory variables. Table S3. Mixed linear model investigating laying date in four passerines species (CF: Collared Flycatcher, GT: Great tit and PF: Pied Flycatcher) as a function of habitat characteristics (intensity of urbanisat...

Figure S3. Box plots of latitude of study plots in four passerine birds in Europe, North Africa and the Middle East.

The increase in size of human populations in urban and agricultural areas has resulted in considerable habitat conversion globally. Such anthropogenic areas have specific environmental characteristics, which influence the physiology, life history, and population dynamics of plants and animals. For example, the date of bud burst is advanced in urban...

The size and shape of the nest are species-specific characteristics that are often associated with environmental factors at the time of breeding. Nests are expected to be larger or thicker in colder environments, although the relationships between nest design and weather differ between species. Here we present the results of an analysis of the exte...

Standardized long-term multi-plot investigations of variation in nest size in free-ranging model species are rare, despite their value for understanding how the environment influences plastic traits such as nest size. Here, we report the results of an 18-yr descriptive study of nest size in first clutches produced by secondary-cavity nesting great...

Longitudinal multi-plot studies of nest architecture in non-domesticated birds are rare. Here we report the results of an 18-year multi-plot study that compared heights of fresh female-built nests in Corsican Great Tits (Parus major) and Blue Tits (Cyanistes caeruleus ogliastrae). Boxes with relatively small nest-chambers were erected in a landscap...

Summary information on studies of the relationship between clutch size and nest size in different species of birds.

Nests are structures built to support and protect eggs and/or offspring from predators, parasites, and adverse weather conditions. Nests are mainly constructed prior to egg laying, meaning that parent birds must make decisions about nest site choice and nest building behavior before the start of egg-laying. Parent birds should be selected to choose...

Secondary hole nesting birds that do not construct nest holes themselves and hence regularly breed in nest boxes constitute important model systems for field studies in many biological disciplines with hundreds of scientists and amateurs involved. Those research groups are spread over wide geographic areas that experience considerable variation in...

The first goal of this study was to determine whether morphological variation in the freshwater blenny Salaria fluviatilis results in spatially structured populations distributed around Corsica, France, which would suggest genetically differentiated populations through reproductive isolation by distance. The second goal was to determine whether som...

Food chains culminating with temperate insectivorous passerines are well described, yet whether trophic webs can be site-specific remains a largely unexplored question. In the case of site- or habitat-specificity of food webs, stable isotope signatures of bird feathers may enable assignment of unmarked individuals to a site or a habitat of origin....

We developed an approach for analysing the effects of two crossed factors A and B on the functional, taxonomic or phylogenetic composition of communities. The methodology, known as crossed-DPCoA, defines a space where species, communities and the levels of the two factors are organised as a set of points. In this space, the Euclidean distance betwe...

Bird taxonomy. (PDF)

R scripts. R scripts are used in Text S4. (TXT)

Manual for R scripts. This appendix uses data available in Dataset S1 and R scripts available in Text S3. (PDF)

Connections between crossed-DPCoA and other ordination approaches. Previously developed crossed analyses that treat species as equidistant, as with classical diversity indices are compared with crossed-DPCoA. (PDF)

The data set in ascii format to be loaded by the R software. The data are described in Text S4. (RDA)

Notations and proofs. (PDF)

Detailed description of crossed-DPCoA, discussion and further propositions. We provide all equations necessary to obtain the space of DPCoA and to perform crossed-DPCoA. Our choices are justified and compared with other possible versions of crossed-DPCoA. The issues related to repetition and unbalanced schemes are discussed and solutions given. (PD...

Species whose positions in the phylogeny were not defined by Davis. This appendix contains details on the establishment of the phylogeny. (PDF)

1. Phenotypic plasticity, the response of individual phenotypes to their environment, can allow organisms to cope with spatio-temporal variation in environmental conditions. Recent studies have shown that variation exists among individuals in their capacity to adjust their traits to environmental changes and that this individual plasticity can be u...

A Corsican population of blue tits (Parus caeruleus) suffers extremely high levels of infestation by two species of blow flies (genus Protocalliphora) that have been suspected to influence the life-history traits of their hosts. By quantifying the abundance of the blow fly larvae infesting each brood of this population during 2 consecutive years, w...

We compared winter roosting behaviour of Blue Tits Cyanistes caeruleus in the mainland of southern France and on the island of Corsica in small-holed nest boxes. While in southern France Blue Tits use nest boxes for roosting, Corsican Blue Tits do not. We suggest that this behaviour is innate because Corsican wild-caught as well as F1 and F2 birds...

The regulation of reproductive schedules is an important determinant of avian breeding success. In heterogeneous environments, the optimal breeding period may fluctuate temporally across habitats, often on a spatial scale much shorter than the average dispersal range of individuals. The synchronisation of reproductive events with the most favourabl...

Birds use local environmental cues to fine-tune the timing of egg laying such that the nestling period normally coincides with the local peak in food availability. Ambient temperature, vegetation phenology, and insect phenology are often considered the most likely cues, but no previous studies have explicitly compared and partitioned their relative...

Several bird species add fresh fragments of plants which are rich in volatile secondary compounds to their nests. It has been suggested, although never tested, that birds use fresh plants to limit the growth of nest microorganisms. On Corsica, blue tits (Cyanistes caeruleus) incorporate fresh fragments of aromatic plants into their nests. These pla...

For altricial birds, detailed studies of parental care include egg incubation, brooding and chick feeding, all of them being crucial to offspring survival. Few studies have explored nest building and maintenance from this perspective, although the nest is the first environment experienced by hatchlings. On Corsica, blue tits, Cyanistes caeruleus, i...

Keywords: blue tit body size brood enlargement chick condition chick growth Cyanistes caeruleus feather development haematocrit nest construction nest greenery parental care For altricial birds, detailed studies of parental care include egg incubation, brooding and chick feeding, all of them being crucial to offspring survival. Few studies have exp...

Although mistimed reproduction (i.e., time-lag between peak food supply and offspring food demand) has been attributed to habitat modifications or climate change in recent avian investigations, earlier breeding parents have higher reproductive success in many habitats. Here we compare first and second broods in from double-brooded great tits (Parus...

1. Breeding at the right time of the year is crucial for many temperate zone organisms, as any mismatch with their optimal breeding period leads to a reduction in fitness. The roles of the breeding partners in these adaptive decisions have, however, only rarely been studied. 2. In blue tits (Cyanistes caeruleus) that breed in heterogenous Mediterra...

With 366 species of breeding birds, the Mediterranean region is a “hot spot” of species diversity. Many biogeographic realms contributed to the establishment of the extant fauna, which makes this region a crossroads for birds, but the two most important realms are the large forest blocks that extend today over Eurasia and the semi-arid belts of the...

A prerequisite for understanding adaptation is to understand how populations respond to environmental heterogeneity. We chose the blue tit Cyanistes caeruleus and Mediterranean habitat mosaics which exhibit a large diversity of habitats for analysing the effects of environmental heterogeneity on phenotypic variation. Three main factors of heterogen...

Aim To investigate the effects of human-induced landscape changes in Mediterranean islands on the ecological and evolutionary responses of bird communities and populations. The combination of mass extinction of large mammals and massive deforestation by humans was hypothesized to produce new selection regimes to which organisms were likely to respo...

Little is known about whether adaptations to an insular life also involve adaptations in basal corticosterone levels or in the adrenocortical stress response, thus being part of a genetically based island syndrome. However, differences in corticosterone between island and mainland may also be a direct phenotypic response to differences in environme...

Summary 1. Identifying how selection shapes life-history traits by causally relating environment to phenotype, performance and fitness has often proven elusive due to limitations of classical analysis methods, which only identify covariance in traits, and to the difficul- ties in experimentally manipulating environment to expose cause and effect in...

The aim of this paper is to tackle the problem that arises from asymmetrical data cubes formed by two crossed factors fixed by the experimenter (factor A and factor B, e.g., sites and dates) and a factor which is not controlled for (the species). The entries of this cube are densities in species. We approach this kind of data by the comparison of p...

Egg production may be influenced by environmental conditions such as local climate or food availability, which may impose physiological constraints on the acquisition and mobilization of egg constituents. We analyzed egg composition of free-ranging female Blue Tits (Cyanistes caeruleus (L., 1758)) in both deciduous and evergreen oak habitats, which...

What makes the structure and dynamics of coupled natural and human systems difficult to interpret in the Mediterranean is the extreme diversity in space and time of both environments and human societies. The succession of civilizations that waxed and waned in the Mediterranean Basin over several millennia has had great impacts on biota and ecosyste...

In some hole nesting passerine species, long-term monitoring data are available for several geographically independent populations. Climate forcing can then be documented and predictions made on the scale of distribution ranges. Several demographic studies of Paridae report dramatic impacts of wintertime climatic factors. However, these studies wer...

Birds may react to the presence of humans with an immediate primary behavioural reaction and with physiological responses, such as the activation of the hypothalamo-pituitary-adrenal axis. This study investigates the suite of behavioural and adrenocortical responses to the presence of humans and to handling in two subspecies of blue tits Parus caer...

In recent years, the study of phenotypic and genetic variation has been enhanced by combining genetic, physiological, demographic, and behavioral components of life histories. Using these new approaches, we address the problem of adaptation to environmental heterogeneity by examining in detail the variation of several fitness-related traits in a sm...

A cascade of morphological, ecological, demographical and behavioural changes operates within island communities compared to mainland. We tested whether metabolic rates change on islands. Using a closed circuit respirometer, we investigated resting metabolic rate (RMR) of three species of Crocidurinae shrews: Suncus etruscus, Crocidura russula, and...

The nests of altricial bird species are host to a variety of nest ectoparasites that may develop high infestation levels and have a negative impact on chick growth, hematocrit, metabolic capacity, and survival before or after fledging. If ectoparasites affect chick development and fitness, then one would expect chicks to express behavior that might...

Geographically separated populations may diverge genetically in response to differing environmental conditions. Two populations of blue tits (Parus caeruleus L., 1758) that inhabit distinct valleys in northern Corsica are exposed to extreme differences in food abundance and parasite loads and show differences in nestling mass and hematocrit levels...

Many bird species face seasonal and spatial variation in the availability of the specific food required to rear chicks. Caterpillar availability is often identified as the most important factor determining chick quality and breeding success in forest birds, such as tits Parus spp. It is assumed that parents play an important role in mediating the e...

Vertebrate studies have rarely investigated the influence of spatial variation in habitat richness on both short-term (breeding) and long-term (offspring recruitment) reproductive performance using simultaneously multi-patch, multi-habitat type and multi-year approaches at landscape level. Here we present results of such an approach using the influ...

The influence of a parasite (larvae of Protocalliphora, Diptera: Calliphoridae) on an avian host (Blue Tit) was studied in 1994-1997 as part of a long-term research project on a population of Blue Tits inhabiting nest boxes on the island of Corsica. The Blue Tit broods were heavily infested with Protocalliphora larvae. The abundance of caterpillars...

A large body of theories on extra-pair paternity (EPP) in birds has proposed four main “genetic” hypotheses to explain this behaviour: the “good genes” hypothesis, the genetic diversity hypothesis, the genetic compatibility hypothesis and the fertility insurance hypothesis. Empirical tests have been scarce, mainly because high sample sizes are diff...

Quantifying the genetic variation and selection acting on phenotypes is a prerequisite for understanding microevolutionary processes. Surprisingly, long-term comparisons across conspecific populations exposed to different environments are still lacking, hampering evolutionary studies of population differentiation in natural conditions. Here, we pre...

The consequences of nest ectoparasites, such as Protocalliphora larvae, on nestling birds have been the subject of numerous studies. Despite observed reductions in mass and hematocrit of chicks from parasitized nests, no studies have found any effect of Protocalliphora on nestling survival, suggesting that fitness consequences of Protocalliphora ar...

Food supply is widely considered to be a major factor in determining life history traits and reproductive performance of birds. However, large spatial and temporal variation in natural available food supply is not always paralleled by proportional changes in energy demand by breeding birds. This necessarily results in variation in the supply– deman...

In altricial birds, adults are expected to alleviate the impact of parasitism on their young by increasing parental care. We experimentally investigated the effects of blowfly parasitism on adult behaviour in the nest cavity in a population of Blue Tits in which nestlings are heavily parasitized by blowfly larvae. The behaviour of males and females...

Blow fly (Protocalliphora spp.) larvae are nest ectoparasites that compete with nestlings for resources by feeding on blood. Their main direct consequences on nestlings are a reduction in growth, blood parameters, and physiological performance. The impact of Protocalliphora larvae on nestling development can be extremely variable between nests with...

We investigate which hypothesis, the “better mate hypothesis” or the “better territory hypothesis” best explains the unusually high divorce rate (59%) in a population of blue tits (Parus caeruleus) living in a sclerophyllous habitat characterised by severe environmental constraints (trophic, parasitic, climatic) on the island of Corsica, France. Us...

Extra-pair copulation (EPC) is a widespread behaviour amongst birds, yet the rate of occurrence of extra-pair offspring is highly variable both within and across species. Two populations of Mediterranean blue tits, Parus caeruleus, one on the mainland and the other on the island of Corsica, are characterized by high levels of extra-pair paternity (...

Spring temperatures in temperate regions have increased over the past 20 years and many organisms have responded to this increase by advancing the timing of their growth and reproduction. However, not all populations show an advancement of phenology. Understanding why some populations advance and others do not will give us insight into the possible...

Le bois mort, composante essentielle des forêts naturelles, est peu abondant dans la majorité des forêts gérées (seulement 2,2 m3/ha en France en moyenne selon l’IFN). Cette lacune met en difficulté une biodiversité spécifique, riche et originale par la perte d’habitats ou de nourriture, notamment pour les communautés d’espèces cavicoles et saproxy...

Dead wood, an essential feature in natural forests, is generally scarce in managed forests (on average, only 2.2 m3/ha in France according to the iFN). This scarcity presents difficulties for maintaining a specific, rich and original biodiversity due to loss of habitats or nourishment, particularly for communities of cavity dwellers and saproxylic...

We investigate whether a mosaic of habitats of different quality functions as a source-sink system for the Blue Tit Parus caeruleus L. Breeding parameters, especially laying date, clutch size and breeding success have been studied in relation to the food supply in three habitats: two habitats, one rich and one poor, next to each other on the mainla...

Although much attention has been devoted to understanding the adaptive value of size hierarchies within broods of altricial birds, current hypotheses are the subject of much debate. Recently it has been suggested that parasites could play a role in promoting the establishment and maintenance of a nestling size hierarchy within broods. For example,...

Animals use the chemical compounds of plants as a defence mechanism against enemies, and sometimes use olfaction to discriminate and select the chemical plant substances. Some birds bring to the nest plant material that has volatile compounds that protect the host and their offspring against parasitic organisms. Here we show that blue tits on the i...

Many hypotheses, either sex-related or environment-related, have been proposed to explain sexual size dimorphism in birds. Two populations of blue tits provide an interesting case study for testing these hypotheses because they live in contrasting environments in continental France and in Corsica and exhibit different degree of sexual size dimorphi...

Offspring fitness depends on interactions between parental care and environmental constraints. It has been suggested that in altricial birds parents are able to compensate for the detrimental effects of ectoparasites by improving food provisioning. We tested this prediction in a population of blue tits highly parasitized by blowfly larvae. The freq...