Experimental nest cooling reveals dramatic effects of heatwaves on reproduction in a Mediterranean bird of prey

Future climatic scenarios forecast increases in average temperatures as well as in the frequency, duration, and intensity of extreme events, such as heatwaves. Whereas behavioral adjustments can buffer direct physiological and fitness costs of exposure to excessive temperature in wild animals, these may prove more difficult during specific life stages when vagility is reduced (e.g., early developmental stages). By means of a nest cooling experiment, we tested the effects of extreme temperatures on different stages of reproduction in a cavity-nesting Mediterranean bird of prey, the lesser kestrel (Falco naumanni), facing a recent increase in the frequency of heatwaves during its breeding season. Nest temperature in a group of nest boxes placed on roof terraces was reduced by shading them from direct sunlight in 2 consecutive years (2021 and 2022). We then compared hatching failure, mortality, and nestling morphology between shaded and non-shaded (control) nest boxes. Nest temperature in control nest boxes was on average 3.9 degrees C higher than in shaded ones during heatwaves, that is, spells of extreme air temperature (>37 degrees C for =2 consecutive days) which hit the study area during the nestling-rearing phase in both years. Hatching failure markedly increased with increasing nest temperature, rising above 50% when maximum nest temperatures exceeded 44 degrees C. Nestlings from control nest boxes showed higher mortality during heatwaves (55% vs. 10% in shaded nest boxes) and those that survived further showed impaired morphological growth (body mass and skeletal size). Hence, heatwaves occurring during the breeding period can have both strong lethal and sublethal impacts on different components of avian reproduction, from egg hatching to nestling growth. More broadly, these findings suggest that the projected future increases of summer temperatures and heatwave frequency in the Mediterranean basin and elsewhere in temperate areas may threaten the local persistence of even relatively warm-adapted species

Carry‐over effects of seasonal migration on reproductive success through breeding site retention in a partially migratory bird

•1. Understanding the maintenance and dynamics of phenotypic polymorphisms requires unpicking key ecological mechanisms shaping the fitness costs and benefits of expressing alternative phenotypes, generating selection. Seasonal migration versus year-round residence expressed in partially migratory populations represents one common polymorphism that can experience strong selection through differential reproductive success. Yet, key hypothesised pathways that could generate such selection remain to be empirically tested. •2. One hypothesis is that migratory tactics affect subsequent reproductive success through carry-over effects on breeding site retention and resulting breeding dispersal. By remaining in breeding areas all year round, residents could retain their preferred breeding site between years, and consequently have higher reproductive success. Conversely, migrants that escape harsh non-breeding season conditions could return in better condition, with high resource holding potential, and outcompete residents to retain their site. Such effects could further depend on migration timing and vary between years. Yet, such pathways have not been quantified, precluding empirical parameterisation of partial migration theory. •3. We used 4 years of breeding and non-breeding season data from partially migratory European shags (Gulosus aristotelis) to test whether the three most frequent migratory tactics in this population (full resident, early migrant departing soon after breeding, and late migrant departing in late autumn) differed in their breeding site retention; whether site retention predicted reproductive success; and hence whether effects of migratory tactic on reproductive success were explicable through site retention. •4. Overall, residents were much more likely to retain their breeding site between years than both early and late migrants, and site retention was associated with increased reproductive success. Yet, these effects varied somewhat among years: late migrants were always least likely to retain their site but had variable relative reproductive success. Path analyses revealed that effects of migratory tactic on reproductive success were only partly attributable to breeding site retention. •5. These results indicate that multiple mechanisms underlie reproductive selection on migratory tactics, potentially contributing to maintaining behavioural polymorphisms. Yet, the clear associations between migratory tactics and local breeding dispersal reveal that these movements can be strongly interlinked across seasons, shaping overall spatioseasonal dynamics in partially migratory systems

Host dispersal shapes the population structure of a tick-borne bacterial pathogen

Birds are hosts for several zoonotic pathogens. Because of their high mobility, especially of longdistance migrants, birds can disperse these pathogens, affecting their distribution and phylogeography. We focused on Borrelia burgdorferi sensu lato, which includes the causative agents of Lyme borreliosis, as an example for tick-borne pathogens, to address the role of birds as propagation hosts of zoonotic agents at a large geographical scale. We collected ticks from passerine birds in 11 European countries. B. burgdorferi s.l. prevalence in Ixodes spp. was 37% and increased with latitude. The fieldfare Turdus pilaris and the blackbird T. merula carried ticks with the highest Borrelia prevalence (92 and 58%, respectively), whereas robin Erithacus rubecula ticks were the least infected (3.8%). Borrelia garinii was the most prevalent genospecies (61%), followed by B. valaisiana (24%), B. afzelii (9%), B. turdi (5%) and B. lusitaniae (0.5%). A novel Borrelia genospecies "Candidatus Borrelia aligera" was also detected. Multilocus sequence typing (MLST) analysis of B. garinii isolates together with the global collection of B. garinii genotypes obtained from the Borrelia MLST public database revealed that: (a) there was little overlap among genotypes from different continents, (b) there was no geographical structuring within Europe, and (c) there was no evident association pattern detectable among B. garinii genotypes from ticks feeding on birds, questing ticks or human isolates. These findings strengthen the hypothesis that the population structure and evolutionary biology of tick-borne pathogens are shaped by their host associations and the movement patterns of these hosts.Peer reviewe

Data for: No evidence for behavioural syndrome and genetic basis for three personality traits in a wild bird population

Personality, morphology and pruned social pedigree from a wild population of collared flycatchers (Ficedula albicollis, Gotland Island, Sweden

Personality data for : "No evidence for behavioural syndrome and genetic basis for three personality traits in a wild bird population"

This dataset constitutes the data we collected and used for the research article "Morinay, J., et al., No evidence for behavioural syndrome and genetic basis for three personality traits in a wild bird population, Animal Behaviour (2019), https://doi.org/10.1016/j.anbehav.2019.05.001".This research article aimed at estimating the phenotypic and genetic correlation among three personality traits (aggressiveness, boldness, and neophobia), in a wild population of a migratory passerine bird, the collared flycatcher (Ficedula albicollis).This dataset is composed of 4 files: Morinay_etal_2019_AnimBeh_aggressivness.xlsx-----------------------------------------------This file provides the 3 aggressiveness scores estimated per individual per test, with the individual ID, and the individual annual ID (to estimate the within-year repeatability). Morinay_etal_2019_AnimBeh_boldness-neophobia.xlsx---------------------------------------------------This file provides the 3 boldness scores and the 3 neophobia scores estimated per individual per test, with the individual ID. Morinay_etal_2019_AnimBeh_tarsus-wing.xlsx-------------------------------------------This file provides the tarsus and wing length of the individuals with personality measures, with the individual ID. Morinay_etal_2019_AnimBeh_pedigree.xlsx-----------------------------------------This file provides the pedigree of the population, pruned for our personality dataset. It gives the known maternal and paternal links of each individual with personality estimates

Personality data for : "No evidence for behavioural syndrome and genetic basis for three personality traits in a wild bird population"

This dataset constitutes the data we collected and used for the research article "Morinay, J., et al., No evidence for behavioural syndrome and genetic basis for three personality traits in a wild bird population, Animal Behaviour (2019), https://doi.org/10.1016/j.anbehav.2019.05.001".This research article aimed at estimating the phenotypic and genetic correlation among three personality traits (aggressiveness, boldness, and neophobia), in a wild population of a migratory passerine bird, the collared flycatcher (Ficedula albicollis).This dataset is composed of 4 files: Morinay_etal_2019_AnimBeh_aggressivness.xlsx-----------------------------------------------This file provides the 3 aggressiveness scores estimated per individual per test, with the individual ID, and the individual annual ID (to estimate the within-year repeatability). Morinay_etal_2019_AnimBeh_boldness-neophobia.xlsx---------------------------------------------------This file provides the 3 boldness scores and the 3 neophobia scores estimated per individual per test, with the individual ID. Morinay_etal_2019_AnimBeh_tarsus-wing.xlsx-------------------------------------------This file provides the tarsus and wing length of the individuals with personality measures, with the individual ID. Morinay_etal_2019_AnimBeh_pedigree.xlsx-----------------------------------------This file provides the pedigree of the population, pruned for our personality dataset. It gives the known maternal and paternal links of each individual with personality estimates.THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV

Combining social information use and comfort- seeking for nest site selection in a cavity-nesting raptor

Dataset for the article : Combining social information use and comfort seeking for nest site selection in a cavity-nesting raptor Morinay et al. 2021, Animal Behaviour, accepted. Please cite the published article if using the dataset

Data for: No evidence for behavioural syndrome and genetic basis for three personality traits in a wild bird population

Personality, morphology and pruned social pedigree from a wild population of collared flycatchers (Ficedula albicollis, Gotland Island, Sweden)THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV