0000000000002373
AUTHOR
José Verdejo
The Usefulness of Biometrics for the Study of Avian Connectivity within Europe. A Case Study with BlackcapsSylvia atricapillain Spain
Summary. The use of biometrics in studies of migratory connectivity is still relatively infrequent in Europe. This is partly due to the fact that biometrics is a less accurate tool when compared to ringing recovery data, or such techniques as stable isotope analyses, use of geolocators or satellite telemetry. Combination with one of these (recovery data) allows us to test the usefulness of biometrics in connectivity analyses, as well as to evaluate/quantify the influence of migratory behaviour on phenotypic traits such as flight morphology. We used historical recovery data, together with flight morphology data obtained from a consistent collection protocol during a three-year ringing progra…
“The tale of the three little tits”: Different nest building solutions under the same environmental pressures
Evolutionary selection pressures, and species-specific ecology and behavior, promote a great variability in the size and composition of nests. However, it would be expected that phylogenetically close species, with similar ecological needs, breeding at the same time in the same place, would also build similar nests. In contrast with this, previous studies have found differences in nest mass and composition among closely related sympatric species. These differences have been attributed to small differences in body size (smaller species building larger and/or more insulated nests), or to the different ways in which species perceive the environment (e.g. perceived predation risk). In this stud…
Deconstructing incubation behaviour in response to ambient temperature over different timescales
Avian embryos need a stable thermal environment to develop optimally, while incubat-ing females need to allocate time to self-maintenance off the nest. In species with female-only incubation, eggs are exposed to ambient temperatures that usually cool them down during female absences. The lower the ambient temperature the sooner females should return to re-warm the eggs. When incubation constraints ease at increasing ambient temperatures, females respond by increasing either incubation effort or self-maintenance time. These responses are population-dependent even within the same species; but it is uncertain whether they are caused by local environmental conditions or they are an artefact fro…
Variation in Great Tit Nest Mass and Composition and Its Breeding Consequences: A Comparative Study in four Mediterranean Habitats
Bird nests are structures whose properties affect breeding performance. Thus, the vast majority of bird species build their own characteristic nests, selecting appropriate materials to do so. However, in habitats where the availability of "ideal" materials is low, some ability to use alternative ones would be necessary, even at the cost of having breeding success reduced. The Great Tit (Parus major) breeds under widely different environmental conditions. Its nests are althought to be composed mainly of moss, although very few studies have quantified nest composition. Our target here was describing Great Tit nest mass and composition in four different Mediterranean habitats, and exploring th…